Pub Date : 2024-05-28DOI: 10.1177/14777606241257063
Noorulnajwa Diyana Yaacob, Sam Sung Ting, Athirah Marsya Azizul Rashidi
The effect of natural weathering exposure time on the poly (3-hydroxybutyrate-co-3 hydroxyvalerate) (PHBV)/paddy straw powder (PSP) biocomposites was studied. These biocomposites were naturally exposed to tropical climate weathering conditions in Perlis, Malaysia for 6 months. Tensile test, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) were applied to investigate the degradation that happened during natural weathering of the biocomposites. Tensile tests indicated that the weathered PHBV/PSP biocomposites caused lower ultimate strength and elongation to break, but increased the modulus of elasticity. As the exposure time prolonged to 6 months, the concentration of O-H groups became pronounced, indicating severe deterioration of the biocomposites. With a carbonyl chromophoric group in its structure, PHBV can absorb UV radiation directly, which could lead to reactions of Norrish forms I and II. Generally, the addition of PSP has increased the degradability of PHBV. Besides, the exposed PHBV/PSP biocomposite surfaces have undergone surface crazing upon weathering. The surface of the PHBV without the addition of the PSP did not show any crack and fungus colonisation. The higher PSP content loaded in the biocomposites (i.e. 20 wt. %) caused more fungi colonisation, resulting in larger cracks and pores formed on the surface of the samples.
{"title":"Natural weathering degradation studies of the poly (3-hydroxybutyrate-co-3 hydroxyvalerate) (PHBV)/paddy straw powder (PSP) biocomposites","authors":"Noorulnajwa Diyana Yaacob, Sam Sung Ting, Athirah Marsya Azizul Rashidi","doi":"10.1177/14777606241257063","DOIUrl":"https://doi.org/10.1177/14777606241257063","url":null,"abstract":"The effect of natural weathering exposure time on the poly (3-hydroxybutyrate-co-3 hydroxyvalerate) (PHBV)/paddy straw powder (PSP) biocomposites was studied. These biocomposites were naturally exposed to tropical climate weathering conditions in Perlis, Malaysia for 6 months. Tensile test, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) were applied to investigate the degradation that happened during natural weathering of the biocomposites. Tensile tests indicated that the weathered PHBV/PSP biocomposites caused lower ultimate strength and elongation to break, but increased the modulus of elasticity. As the exposure time prolonged to 6 months, the concentration of O-H groups became pronounced, indicating severe deterioration of the biocomposites. With a carbonyl chromophoric group in its structure, PHBV can absorb UV radiation directly, which could lead to reactions of Norrish forms I and II. Generally, the addition of PSP has increased the degradability of PHBV. Besides, the exposed PHBV/PSP biocomposite surfaces have undergone surface crazing upon weathering. The surface of the PHBV without the addition of the PSP did not show any crack and fungus colonisation. The higher PSP content loaded in the biocomposites (i.e. 20 wt. %) caused more fungi colonisation, resulting in larger cracks and pores formed on the surface of the samples.","PeriodicalId":20860,"journal":{"name":"Progress in Rubber Plastics and Recycling Technology","volume":"29 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141166740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Decommissioned or damaged windmill blades and other wastes have limited applications and are generally disposed into landfills or incinerated. Increasing generation of wind energy will also lead to increase in blades available for disposal. It is estimated that more than 800,000 tons of blades will be available annually for disposal from 2050. Blades contain glass, carbon, resins and other valuable materials and hence it is prudent to develop methods to reuse or recycle the blades. In this study, we have used windmill blade waste (WBW) as reinforcement for polypropylene (PP) and also as filler/additive for coir-WBW-PP hybrid composites. Various proportions of the components were made into composites and studied for the changes in mechanical, acoustic, thermal and noise insulation properties. Tensile strength did not show major increase in properties whereas 70/30 WBW/PP composites had highest flexural strength and modulus. Addition of WBW considerably increased both the tensile and flexural properties of the hybrid composites with up to 180% increase in flexural strength and 173% increase in modulus. Similarly, hybrid composites had better thermal conductivity and the composites containing 80% WBW and 20% PP had the highest thermal conductivity. Coir improved the acoustic sorption due to the presence of pores and voids in the composites whereas WBW acts as filler and decreased the sound sorption. WBW can be effectively used as reinforcement or filler for PP based composites.
{"title":"Utilizing decommissioned windmill blades as reinforcement or filler for biocomposites","authors":"Desmond Daniel Chin Vui Sheng, Sreehari Tambathhouse Sreedharan, Sanjeev Surendra Walvekar, Vijaykumar Guna, Sumukha Bandagadde Muralimohana, Praveen Kumar Krishnamurthy, Narendra Reddy","doi":"10.1177/14777606241252705","DOIUrl":"https://doi.org/10.1177/14777606241252705","url":null,"abstract":"Decommissioned or damaged windmill blades and other wastes have limited applications and are generally disposed into landfills or incinerated. Increasing generation of wind energy will also lead to increase in blades available for disposal. It is estimated that more than 800,000 tons of blades will be available annually for disposal from 2050. Blades contain glass, carbon, resins and other valuable materials and hence it is prudent to develop methods to reuse or recycle the blades. In this study, we have used windmill blade waste (WBW) as reinforcement for polypropylene (PP) and also as filler/additive for coir-WBW-PP hybrid composites. Various proportions of the components were made into composites and studied for the changes in mechanical, acoustic, thermal and noise insulation properties. Tensile strength did not show major increase in properties whereas 70/30 WBW/PP composites had highest flexural strength and modulus. Addition of WBW considerably increased both the tensile and flexural properties of the hybrid composites with up to 180% increase in flexural strength and 173% increase in modulus. Similarly, hybrid composites had better thermal conductivity and the composites containing 80% WBW and 20% PP had the highest thermal conductivity. Coir improved the acoustic sorption due to the presence of pores and voids in the composites whereas WBW acts as filler and decreased the sound sorption. WBW can be effectively used as reinforcement or filler for PP based composites.","PeriodicalId":20860,"journal":{"name":"Progress in Rubber Plastics and Recycling Technology","volume":"100 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140934295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-08DOI: 10.1177/14777606241252702
Nur Mawaddah Majib, Noorulnajwa Diyana Yaacob, Sam Sung Ting, Nor Munirah Rohaizad, Athirah Marsya Azizul Rashidi
Recent years have shown a surge in interest in incorporating living systems into materials research to synthesize functional materials using biological resources. Among these, mycelium-based materials, notably biofoam, have emerged as innovative solutions for repurposing organic wastes that were previously considered unusable. The growth of mycelium, vital for the synthesis of biofoam, is influenced by a multuple of factors including substrate composition, moisture content, temperature, nutrient availability, pH levels, oxygen concentration, and measures for contamination control. Additionally, physical stimulation techniques have been explored to enhance mycelium growth, ranging from cold stress-induced adaptations to electrical shock-induced modifications and optimization of sound treatments and light exposure. This review highlights the growing interest in biofoam composite materials, a novel class of environmentally friendly and cost-effective materials that are gaining popularity, for advancing sustainable construction practices. Biofoam composites use organic fungal growth as a low-energy bio-fabrication process to transform abundant agricultural byproducts and waste into viable alternatives to energy-intensive manufactured building materials. Their versatility in composition and manufacturing methods allows them to be used in a wide range of applications, including insulation and door cores, panelling, flooring, and furniture components. Notably, biofoams outperform synthetic foams and engineered wood in terms of thermal insulation, sound absorption, and fire resistance, making them highly promising for construction industry. Besides, due to its customizable composition and production method, biofoam can be used in the replacement of foams, leather, wood, and plastics in a variety of applications such as water treatment and filtration, medical supplies and healthcare applications. However, despite their remarkable properties, biofoam typically serve as non- or semi-structural supplements to traditional construction materials due to inherent limitations. Nevertheless, the useful material properties of these materials, combined with their low cost, ease of manufacture, and environmental sustainability, imply that they will have an important part to play in the development of environmentally friendly materials in the future.
{"title":"Fungal mycelium-based biofoam composite: A review in growth, properties and application","authors":"Nur Mawaddah Majib, Noorulnajwa Diyana Yaacob, Sam Sung Ting, Nor Munirah Rohaizad, Athirah Marsya Azizul Rashidi","doi":"10.1177/14777606241252702","DOIUrl":"https://doi.org/10.1177/14777606241252702","url":null,"abstract":"Recent years have shown a surge in interest in incorporating living systems into materials research to synthesize functional materials using biological resources. Among these, mycelium-based materials, notably biofoam, have emerged as innovative solutions for repurposing organic wastes that were previously considered unusable. The growth of mycelium, vital for the synthesis of biofoam, is influenced by a multuple of factors including substrate composition, moisture content, temperature, nutrient availability, pH levels, oxygen concentration, and measures for contamination control. Additionally, physical stimulation techniques have been explored to enhance mycelium growth, ranging from cold stress-induced adaptations to electrical shock-induced modifications and optimization of sound treatments and light exposure. This review highlights the growing interest in biofoam composite materials, a novel class of environmentally friendly and cost-effective materials that are gaining popularity, for advancing sustainable construction practices. Biofoam composites use organic fungal growth as a low-energy bio-fabrication process to transform abundant agricultural byproducts and waste into viable alternatives to energy-intensive manufactured building materials. Their versatility in composition and manufacturing methods allows them to be used in a wide range of applications, including insulation and door cores, panelling, flooring, and furniture components. Notably, biofoams outperform synthetic foams and engineered wood in terms of thermal insulation, sound absorption, and fire resistance, making them highly promising for construction industry. Besides, due to its customizable composition and production method, biofoam can be used in the replacement of foams, leather, wood, and plastics in a variety of applications such as water treatment and filtration, medical supplies and healthcare applications. However, despite their remarkable properties, biofoam typically serve as non- or semi-structural supplements to traditional construction materials due to inherent limitations. Nevertheless, the useful material properties of these materials, combined with their low cost, ease of manufacture, and environmental sustainability, imply that they will have an important part to play in the development of environmentally friendly materials in the future.","PeriodicalId":20860,"journal":{"name":"Progress in Rubber Plastics and Recycling Technology","volume":"157 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140934159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-10DOI: 10.1177/14777606241246582
Norfatirah Muhamad Sarih, Lim Chow Peei, Azura A Rashid
Researchers have recently focused on green processing aids made from plants and vegetables to avoid the high concentration of polycyclic aromatic hydrocarbons (PAHs) from petroleum-based processing oils, which is hazardous to human health. This paper focuses on the effect of lubricants and plasticisers produced from palm oil on the rheological, mechanical and thermal aging properties of styrene-butadiene rubber (SBR). These lubricants and plasticisers are known as glycerol trioleate (GTO), n-butyl stearate (NBS), ethylene bis-steramide (EBS), ethylene bis-oleamide (EBO), pentaerythritol tetrastearate (PETS) and stearyl stearate. The abrasion performance, visual inspection appearance, and cure characteristics of the lubricants and plasticisers on SBR were examined and compared to processing oil-treated distillate aromatic extract (TDAE), paraffin wax, microcrystalline wax, polyethylene (PE) wax, epoxidised soybean oil (ESBO), and stearic acid. It discovered that rubber compounds based on GTO, stearic acid, and EBS exhibited better abrasion resistance and cure properties than rubber compounds based on processing oil. These samples were selected and subjected to mechanical properties, thermal aging effects analysis and comparison with processing oil. Tensile strength shows that SBR with EBS (22.49 MPa) and EBS with GTO (EBS/GTO; 21.25 MPa) are closely similar to SBR compounds with processing oil (21.02 MPa). The findings imply that EBS and EBS/GTO, green plasticisers and lubricants, are viable alternatives to petroleum-based processing oils while being cost-effective for tire production.
{"title":"The influence of palm oil-derived plasticizers and lubricants on the rheological and mechanical properties of styrene butadiene rubber","authors":"Norfatirah Muhamad Sarih, Lim Chow Peei, Azura A Rashid","doi":"10.1177/14777606241246582","DOIUrl":"https://doi.org/10.1177/14777606241246582","url":null,"abstract":"Researchers have recently focused on green processing aids made from plants and vegetables to avoid the high concentration of polycyclic aromatic hydrocarbons (PAHs) from petroleum-based processing oils, which is hazardous to human health. This paper focuses on the effect of lubricants and plasticisers produced from palm oil on the rheological, mechanical and thermal aging properties of styrene-butadiene rubber (SBR). These lubricants and plasticisers are known as glycerol trioleate (GTO), n-butyl stearate (NBS), ethylene bis-steramide (EBS), ethylene bis-oleamide (EBO), pentaerythritol tetrastearate (PETS) and stearyl stearate. The abrasion performance, visual inspection appearance, and cure characteristics of the lubricants and plasticisers on SBR were examined and compared to processing oil-treated distillate aromatic extract (TDAE), paraffin wax, microcrystalline wax, polyethylene (PE) wax, epoxidised soybean oil (ESBO), and stearic acid. It discovered that rubber compounds based on GTO, stearic acid, and EBS exhibited better abrasion resistance and cure properties than rubber compounds based on processing oil. These samples were selected and subjected to mechanical properties, thermal aging effects analysis and comparison with processing oil. Tensile strength shows that SBR with EBS (22.49 MPa) and EBS with GTO (EBS/GTO; 21.25 MPa) are closely similar to SBR compounds with processing oil (21.02 MPa). The findings imply that EBS and EBS/GTO, green plasticisers and lubricants, are viable alternatives to petroleum-based processing oils while being cost-effective for tire production.","PeriodicalId":20860,"journal":{"name":"Progress in Rubber Plastics and Recycling Technology","volume":"65 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140580014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-27DOI: 10.1177/14777606241243113
Nabil Hayeemasae, Siriwat Soontaranon, Abdulhakim Masa
The effects of various natural rubber (NR) grades, namely RSS 3, STR 5L, STR 10, STR 20 and STR 20CV, towards their final properties were investigated. The molecular characteristics of these NR grades were assessed by gel permeation chromatography and by determining protein contents. The highest molecular weight was found for RSS 3, while STR 20CV had the lowest molecular weight. No relationship between molecular weight and protein content was seen in this study. A higher molecular weight rubber provided greater maximum torque and torque difference, and a better resistance to degradation during processing. However, no significant difference was found among molecular weights higher than 1.25 × 106 g/mol. The final torque during processing and the Mooney viscosity of rubber increased with molecular weight due to tie chain entanglements, as later confirmed by a dynamic mechanical analyzer. Thermo-stability and stress relaxation of the various NR grades were also largely governed by their molecular weights. Stability of rubber at an elevated temperature improved with molecular weight. Also, the tensile properties and the strain-induced crystallization varied with the molecular weight. The tensile strength of various NR grades varied from 15 to 18 MPa while the elongation at break was 600%–800%. The molecular weight of NR was found to have a great effect on the processing, thermomechanical, dynamic, and mechanical properties of the vulcanizates. In addition, a narrow molecular weight distribution also affected the mechanical properties. The crystallinities of the NRs during stretching were closely related to their tensile behavior, and the alignment of crystal structures during stretching was almost parallel to the stretching direction in all NR samples. The molecular weight of NR appears to be a key factor associated with the mechanical properties and reinforcement behavior of vulcanizates.
研究了各种天然橡胶（NR）牌号（即 RSS 3、STR 5L、STR 10、STR 20 和 STR 20CV）对其最终特性的影响。通过凝胶渗透色谱法和蛋白质含量测定评估了这些天然橡胶牌号的分子特性。发现 RSS 3 的分子量最高，而 STR 20CV 的分子量最低。本研究未发现分子量与蛋白质含量之间有任何关系。分子量较高的橡胶可提供更大的最大扭矩和扭矩差，并且在加工过程中具有更好的抗降解性。不过，分子量高于 1.25 × 106 g/mol 的橡胶之间没有明显差异。加工过程中的最终扭矩和橡胶的门尼粘度随着分子量的增加而增加，这是由于拉杆链的缠结，后来用动态机械分析仪证实了这一点。各种 NR 牌号的热稳定性和应力松弛在很大程度上也受其分子量的影响。橡胶在高温下的稳定性随分子量的增加而提高。此外，拉伸性能和应变引起的结晶也随分子量的变化而变化。各种 NR 牌号的拉伸强度从 15 到 18 兆帕不等，而断裂伸长率为 600%-800%。研究发现，NR 的分子量对硫化胶的加工、热机械、动态和机械性能有很大影响。此外，狭窄的分子量分布也会影响机械性能。拉伸过程中 NR 的结晶度与其拉伸行为密切相关，在所有 NR 样品中，拉伸过程中晶体结构的排列几乎平行于拉伸方向。NR 的分子量似乎是与硫化胶的机械性能和加固行为相关的一个关键因素。
{"title":"Structure – property relationships of different natural rubber grades","authors":"Nabil Hayeemasae, Siriwat Soontaranon, Abdulhakim Masa","doi":"10.1177/14777606241243113","DOIUrl":"https://doi.org/10.1177/14777606241243113","url":null,"abstract":"The effects of various natural rubber (NR) grades, namely RSS 3, STR 5L, STR 10, STR 20 and STR 20CV, towards their final properties were investigated. The molecular characteristics of these NR grades were assessed by gel permeation chromatography and by determining protein contents. The highest molecular weight was found for RSS 3, while STR 20CV had the lowest molecular weight. No relationship between molecular weight and protein content was seen in this study. A higher molecular weight rubber provided greater maximum torque and torque difference, and a better resistance to degradation during processing. However, no significant difference was found among molecular weights higher than 1.25 × 10<jats:sup>6</jats:sup> g/mol. The final torque during processing and the Mooney viscosity of rubber increased with molecular weight due to tie chain entanglements, as later confirmed by a dynamic mechanical analyzer. Thermo-stability and stress relaxation of the various NR grades were also largely governed by their molecular weights. Stability of rubber at an elevated temperature improved with molecular weight. Also, the tensile properties and the strain-induced crystallization varied with the molecular weight. The tensile strength of various NR grades varied from 15 to 18 MPa while the elongation at break was 600%–800%. The molecular weight of NR was found to have a great effect on the processing, thermomechanical, dynamic, and mechanical properties of the vulcanizates. In addition, a narrow molecular weight distribution also affected the mechanical properties. The crystallinities of the NRs during stretching were closely related to their tensile behavior, and the alignment of crystal structures during stretching was almost parallel to the stretching direction in all NR samples. The molecular weight of NR appears to be a key factor associated with the mechanical properties and reinforcement behavior of vulcanizates.","PeriodicalId":20860,"journal":{"name":"Progress in Rubber Plastics and Recycling Technology","volume":"13 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140312956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-16DOI: 10.1177/14777606241239065
Mohammed Hamza Al Maamori, Salih Abbas Habeeb, Mohammed Ali Moslem
Increasing global consumption of low-density polyethylene leads to more polymeric waste and challenges solid waste management. Therefore, the process of recycling or mixing recycled low-density polyethylene (RLDPE) with the same virgin low-density polyethylene (VLDPE) and enhancing the properties of this blend by adding different amounts of bioplastic such as Octanoate starch (OCST) is a good contribution to getting rid of plastic waste and obtaining new materials. This paper mixed the 20, 30 and 50 wt.% from RLDPE with VLDPE to determine the homogeneous blend. Also, 30, 40, and 50 wt. % from OCST were blended with homogeneous as a 20:80 RLDPE: VLDPE to obtain a new hybrid blend containing bioplastic. The scanning electron microscope (SEM) results showed the high surface roughness of the film RLDPE: VLDPE after adding the OCST. The tensile strength, elastic modulus, and hardness of the 20:80 RLDPE: VLDPE blend were 13.0 ± 1.467 MPa, 0.08 ± 0.016 MPa, and 42.3 ± 2.32 Shore A, while the tensile strength, elastic modulus, and hardness of the 12:48:40 RLDPE: VLDPE: OCST were 14.3 ± 1.626 MPa, 0.1 ± 0.032 MPa, and 50.1 ± 2.78 Shore A respectively. On the other hand, the Fourier-Transform Infrared (FTIR) indicated that the strong bands at 1746 cm−1, 2856 cm−1, and 2927 cm−1 indicated stretching deformation of the ester carbonyl group and the methyl and methylene groups of OCST with blend polymers, respectively. The thermal properties as melting point, heat energy consumption, and heat flow difference increased from 122.52 to 123.73°C, −389.41 to −144.43 (mJ), and −77.88 to −28.89 (J/g) when the OCST content increased from 20:80 RLDPE: VLDPE to 12:48:40 RLDPE: VLDPE: OCST. Thermal decomposition led to the formation of functional groups such as hydroxyl and carbonyl on LDPE baskets and an increase in the carbonyl index after adding OCST to the RLDPE: VLDPE blend. The best hybrid blend was 12:48:40 RLDPE: VLDPE: OCST.
{"title":"Enhancing the physical properties of recycled low-density polyethylene and virgin low-density polyethylene blend using octanoate starch","authors":"Mohammed Hamza Al Maamori, Salih Abbas Habeeb, Mohammed Ali Moslem","doi":"10.1177/14777606241239065","DOIUrl":"https://doi.org/10.1177/14777606241239065","url":null,"abstract":"Increasing global consumption of low-density polyethylene leads to more polymeric waste and challenges solid waste management. Therefore, the process of recycling or mixing recycled low-density polyethylene (RLDPE) with the same virgin low-density polyethylene (VLDPE) and enhancing the properties of this blend by adding different amounts of bioplastic such as Octanoate starch (OCST) is a good contribution to getting rid of plastic waste and obtaining new materials. This paper mixed the 20, 30 and 50 wt.% from RLDPE with VLDPE to determine the homogeneous blend. Also, 30, 40, and 50 wt. % from OCST were blended with homogeneous as a 20:80 RLDPE: VLDPE to obtain a new hybrid blend containing bioplastic. The scanning electron microscope (SEM) results showed the high surface roughness of the film RLDPE: VLDPE after adding the OCST. The tensile strength, elastic modulus, and hardness of the 20:80 RLDPE: VLDPE blend were 13.0 ± 1.467 MPa, 0.08 ± 0.016 MPa, and 42.3 ± 2.32 Shore A, while the tensile strength, elastic modulus, and hardness of the 12:48:40 RLDPE: VLDPE: OCST were 14.3 ± 1.626 MPa, 0.1 ± 0.032 MPa, and 50.1 ± 2.78 Shore A respectively. On the other hand, the Fourier-Transform Infrared (FTIR) indicated that the strong bands at 1746 cm<jats:sup>−1</jats:sup>, 2856 cm<jats:sup>−1,</jats:sup> and 2927 cm<jats:sup>−1</jats:sup> indicated stretching deformation of the ester carbonyl group and the methyl and methylene groups of OCST with blend polymers, respectively. The thermal properties as melting point, heat energy consumption, and heat flow difference increased from 122.52 to 123.73°C, −389.41 to −144.43 (mJ), and −77.88 to −28.89 (J/g) when the OCST content increased from 20:80 RLDPE: VLDPE to 12:48:40 RLDPE: VLDPE: OCST. Thermal decomposition led to the formation of functional groups such as hydroxyl and carbonyl on LDPE baskets and an increase in the carbonyl index after adding OCST to the RLDPE: VLDPE blend. The best hybrid blend was 12:48:40 RLDPE: VLDPE: OCST.","PeriodicalId":20860,"journal":{"name":"Progress in Rubber Plastics and Recycling Technology","volume":"106 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140146525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-16DOI: 10.1177/14777606241239066
Xiaoli Xie, Yubin Zheng, Weiwei Zhu, Siliu Yu, Shengchun Zhu, Yang Yang
The influence mechanism of waste rubber particles (WRPs) on the workability, mechanical properties, and sound insulation performance of recycled aggregate sound insulation mortar (RCM) were investigated. According to the principle of volume fraction replacement of recycled fine aggregate by 0 to 50%, WRPs with a particle size of 1–4 mm were incorporated in various mixtures of RCM. Each RCM mixture was tested for workability, mechanical, and sound insulation performance. Mercury intrusion porosimetry was used to analyze the distribution of pores and their sizes inside the material, and X-ray diffraction and scanning electron microscopy were used to analyze the characteristics of the interfacial transition zones (ITZs) between the rubber particles and the cement paste. The results showed that, owing to the hydrophobicity of WRPs, greater WRPs content led to greater fluidity of the mortar mix and a smaller water retention rate. Notably, the rubber in the mortar did not contribute to the hydration reactivity of the cement paste, but it changed the crystal morphology and pore structure of ITZ hydration products. The RCM incorporating 3–10% WRPs produced the optimal pore structure through the aggregate effect, which increased its overall compactness and mechanical performance. Further increase of WRP content significantly improved the sound insulation performance while significantly reducing the strength. Moreover, there was a clear logarithmic relationship between the strength and impact sound level index. This new knowledge can be used to prepare RCM that meets the actual strength and sound insulation requirements of the floor. Thus, the resource utilization of solid waste can be expanded.
{"title":"Effects of waste rubber particles on workability, mechanical, and sound insulation properties of recycled aggregate mortar","authors":"Xiaoli Xie, Yubin Zheng, Weiwei Zhu, Siliu Yu, Shengchun Zhu, Yang Yang","doi":"10.1177/14777606241239066","DOIUrl":"https://doi.org/10.1177/14777606241239066","url":null,"abstract":"The influence mechanism of waste rubber particles (WRPs) on the workability, mechanical properties, and sound insulation performance of recycled aggregate sound insulation mortar (RCM) were investigated. According to the principle of volume fraction replacement of recycled fine aggregate by 0 to 50%, WRPs with a particle size of 1–4 mm were incorporated in various mixtures of RCM. Each RCM mixture was tested for workability, mechanical, and sound insulation performance. Mercury intrusion porosimetry was used to analyze the distribution of pores and their sizes inside the material, and X-ray diffraction and scanning electron microscopy were used to analyze the characteristics of the interfacial transition zones (ITZs) between the rubber particles and the cement paste. The results showed that, owing to the hydrophobicity of WRPs, greater WRPs content led to greater fluidity of the mortar mix and a smaller water retention rate. Notably, the rubber in the mortar did not contribute to the hydration reactivity of the cement paste, but it changed the crystal morphology and pore structure of ITZ hydration products. The RCM incorporating 3–10% WRPs produced the optimal pore structure through the aggregate effect, which increased its overall compactness and mechanical performance. Further increase of WRP content significantly improved the sound insulation performance while significantly reducing the strength. Moreover, there was a clear logarithmic relationship between the strength and impact sound level index. This new knowledge can be used to prepare RCM that meets the actual strength and sound insulation requirements of the floor. Thus, the resource utilization of solid waste can be expanded.","PeriodicalId":20860,"journal":{"name":"Progress in Rubber Plastics and Recycling Technology","volume":"39 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140146518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-14DOI: 10.1177/14777606241239063
Magd M Badr, Manar E Abdel-Raouf, Alaa IE Abdelaziz, Abdulrahiem MA Hasan, Zizi I Abdeen
This article aims to evaluate and compare two types of organic surface-modified-nanoclay of octadecylamine-modified-bentonite-nanoclay (ODA-BNC) and aminopropyltrimethoxysilane-octadecylamine-modified-nanomontmorillonite (APS-ODA-MMT). Each type of nanoclay is combined with silica as a bi-filler for natural rubber (NR)/ethylene propylene diene monomer rubber (EPDM) in a 50/50 blend ratio for possible vulcanized rubber nanocomposite application. The total filler content is 50 phr while nanoclay filler content ranges from 0 to 20 phr, keeping the other ingredients ratio fixed. The prepared composites are characterized by the Fourier transform infrared spectrophotometer (FTIR) and their mechanical and thermal properties are thoroughly investigated. The data reveal that the fillers added to the rubber can improve its surface properties according to their type and amount as confirmed by the Atomic force microscope (AFM), and Scanning electron microscope (SEM) investigation. The surface of rubber containing APS-ODA-MMT displayed higher height (251) and roughness surface (94.11), than those (69.8) and (45.62) respectively, containing ODA-BNC. Moreover, the acid resistance of the prepared composites is verified and indicated that increasing the nanoclay ratio (20%) enhances the acid resistance by reducing the surface distortion while keeping the surface morphology. The mechanical properties and Thermogravimetric Analysis (TGA) measurements showed that the rubber containing ODA-BNC has higher values of stress (2.2), elongation (975), and thermal stability (470, 505, 520°C) than those (1.75), (650), and (440, 460, 470°C) respectively, containing the APS-ODA-MMT. Moreover, the durability investigation of the vulcanized rubber via the AFM found the modified composites can be used in harsh environments as a covering layer in petrochemical networks or chemical factories.
{"title":"Preparation and properties of montmorillonite incorporated natural rubber/ethylene propylene diene monomer rubber blends","authors":"Magd M Badr, Manar E Abdel-Raouf, Alaa IE Abdelaziz, Abdulrahiem MA Hasan, Zizi I Abdeen","doi":"10.1177/14777606241239063","DOIUrl":"https://doi.org/10.1177/14777606241239063","url":null,"abstract":"This article aims to evaluate and compare two types of organic surface-modified-nanoclay of octadecylamine-modified-bentonite-nanoclay (ODA-BNC) and aminopropyltrimethoxysilane-octadecylamine-modified-nanomontmorillonite (APS-ODA-MMT). Each type of nanoclay is combined with silica as a bi-filler for natural rubber (NR)/ethylene propylene diene monomer rubber (EPDM) in a 50/50 blend ratio for possible vulcanized rubber nanocomposite application. The total filler content is 50 phr while nanoclay filler content ranges from 0 to 20 phr, keeping the other ingredients ratio fixed. The prepared composites are characterized by the Fourier transform infrared spectrophotometer (FTIR) and their mechanical and thermal properties are thoroughly investigated. The data reveal that the fillers added to the rubber can improve its surface properties according to their type and amount as confirmed by the Atomic force microscope (AFM), and Scanning electron microscope (SEM) investigation. The surface of rubber containing APS-ODA-MMT displayed higher height (251) and roughness surface (94.11), than those (69.8) and (45.62) respectively, containing ODA-BNC. Moreover, the acid resistance of the prepared composites is verified and indicated that increasing the nanoclay ratio (20%) enhances the acid resistance by reducing the surface distortion while keeping the surface morphology. The mechanical properties and Thermogravimetric Analysis (TGA) measurements showed that the rubber containing ODA-BNC has higher values of stress (2.2), elongation (975), and thermal stability (470, 505, 520°C) than those (1.75), (650), and (440, 460, 470°C) respectively, containing the APS-ODA-MMT. Moreover, the durability investigation of the vulcanized rubber via the AFM found the modified composites can be used in harsh environments as a covering layer in petrochemical networks or chemical factories.","PeriodicalId":20860,"journal":{"name":"Progress in Rubber Plastics and Recycling Technology","volume":"3 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140146373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-14DOI: 10.1177/14777606241239067
Abderrahmane Belhaoues, Farid Riahi, Ángel Antonio Marcos-Fernández
This study investigates the effects of incorporating a 50/50 blend of Epoxidized Natural Rubber/Polypropylene-grafted maleic anhydride (ENR/PP-g-MA) as a compatibilizing agent (CA) for a 70/30 Natural Rubber/Polypropylene (NR/PP) thermoplastic elastomer (TPE) on the technical properties such as structural analysis, rheological, dynamic mechanical and morphological properties. Formulations with varying CA concentrations (5 to 15 phr) were prepared using a Brabender plasticorder at 180°C for 10 min. The structural analysis was examined by Fourier transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance (1H-NMR). The rheological behavior was examined using a Rubber Process Analyser (RPA). The dynamic mechanical properties were investigated by DMA. Atomic Force Microscopy (AFM) was used for the morphological examination. FTIR analysis confirmed reactions between the MA group in PP-g-MA and the epoxy groups in ENR, resulting in ENR-grafted PP with an ester and acid-based linkage. This reaction was evident during compatibilizer preparation. RPA results showed increased viscosity for both types of CAs compared to their individual values, confirming crosslinking reactions. Higher CA concentrations led to elevated viscosity and storage modulus. DMA results indicated that the compatibilization led to a significant enhancement in the storage modulus of the blends. Moreover, an increase in the glass transition temperatures (Tg) of the blends was produced. AFM examination revealed a more homogenous distribution of the dispersed PP phase for the CA-containing blends compared to the control NR/PP system.
本研究探讨了在 70/30 天然橡胶/聚丙烯（NR/PP）热塑性弹性体（TPE）中加入 50/50 环氧化天然橡胶/聚丙烯接枝马来酸酐（ENR/PP-g-MA）混合物作为相容剂（CA）对结构分析、流变、动态机械和形态等技术性能的影响。使用布拉本德塑化仪在 180°C 下 10 分钟制备了不同 CA 浓度（5 至 15 phr）的配方。傅立叶变换红外光谱（FTIR）和质子核磁共振（1H-NMR）对结构进行了分析。使用橡胶过程分析仪（RPA）对流变行为进行了检测。使用 DMA 研究了动态机械性能。原子力显微镜（AFM）用于形态检查。傅立叶变换红外光谱分析证实了 PP-g-MA 中的 MA 基团与 ENR 中的环氧基团之间的反应，从而产生了具有酯基和酸基连接的 ENR 接枝 PP。这种反应在相容剂制备过程中非常明显。RPA 结果表明，与单个值相比，两种 CA 的粘度都有所增加，这证实了交联反应。CA 浓度越高，粘度和储存模量越大。DMA 结果表明，相容可显著提高混合物的储存模量。此外，混合物的玻璃化转变温度（Tg）也有所提高。原子力显微镜检查显示，与对照 NR/PP 系统相比，含 CA 的共混物的分散 PP 相分布更均匀。
{"title":"Enhancement of the rheological, dynamic mechanical, and morphological properties of thermoplastic natural rubber based on NR/PP blends using ENR/PP-g-MA as a compatibilizer","authors":"Abderrahmane Belhaoues, Farid Riahi, Ángel Antonio Marcos-Fernández","doi":"10.1177/14777606241239067","DOIUrl":"https://doi.org/10.1177/14777606241239067","url":null,"abstract":"This study investigates the effects of incorporating a 50/50 blend of Epoxidized Natural Rubber/Polypropylene-grafted maleic anhydride (ENR/PP-g-MA) as a compatibilizing agent (CA) for a 70/30 Natural Rubber/Polypropylene (NR/PP) thermoplastic elastomer (TPE) on the technical properties such as structural analysis, rheological, dynamic mechanical and morphological properties. Formulations with varying CA concentrations (5 to 15 phr) were prepared using a Brabender plasticorder at 180°C for 10 min. The structural analysis was examined by Fourier transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance (<jats:sup>1</jats:sup>H-NMR). The rheological behavior was examined using a Rubber Process Analyser (RPA). The dynamic mechanical properties were investigated by DMA. Atomic Force Microscopy (AFM) was used for the morphological examination. FTIR analysis confirmed reactions between the MA group in PP-g-MA and the epoxy groups in ENR, resulting in ENR-grafted PP with an ester and acid-based linkage. This reaction was evident during compatibilizer preparation. RPA results showed increased viscosity for both types of CAs compared to their individual values, confirming crosslinking reactions. Higher CA concentrations led to elevated viscosity and storage modulus. DMA results indicated that the compatibilization led to a significant enhancement in the storage modulus of the blends. Moreover, an increase in the glass transition temperatures (Tg) of the blends was produced. AFM examination revealed a more homogenous distribution of the dispersed PP phase for the CA-containing blends compared to the control NR/PP system.","PeriodicalId":20860,"journal":{"name":"Progress in Rubber Plastics and Recycling Technology","volume":"17 1","pages":""},"PeriodicalIF":2.6,"publicationDate":"2024-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140146379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-31DOI: 10.1177/14777606231211793
Yang Sun
The compressive strength (CS) of crumb rubber concrete (CRC) can be improved through a chemical pretreatment involving immersion of the crumb rubber particles in a NaOH solution. Despite the potential benefits of this treatment, accurately estimating the CS value of NaOH-pretreated CRC remains challenging. To address this issue, a comprehensive database encompassing 118 entries on the fundamental mixtures of CRC along with NaOH concentration and pretreatment duration has been meticulously compiled for machine learning analysis. The random forest (RF) algorithm is employed to predict the 28-day CS value of NaOH-pretreated CRC. The model hyperparameters are optimized using a random search technique with 10-fold cross-validation. The findings reveal that the optimized RF attains acceptable predictive performance, yielding RMSE, MAE, and R2 values of 3.83 MPa, 2.84 MPa, and 0.85, respectively, on the testing dataset. Additionally, the model is interpreted using multiple techniques, including permutation importance, RF model-based feature importance, and Shapley additive explanation from global or local perspectives. The feature importance analyses consistently highlight the crucial role of crumb rubber content in determining the 28-day CS value of NaOH-pretreated CRC, and the influence of NaOH concentration and pretreatment time appear relatively inconsequential compared to features associated with the CRC mixture. This research contributes to a deeper understanding and better mixture design of CS for NaOH-pretreated CRC.
{"title":"Random forest and Shapley additive explanation for compressive strength prediction of NaOH-pretreated crumb rubber concrete","authors":"Yang Sun","doi":"10.1177/14777606231211793","DOIUrl":"https://doi.org/10.1177/14777606231211793","url":null,"abstract":"The compressive strength (CS) of crumb rubber concrete (CRC) can be improved through a chemical pretreatment involving immersion of the crumb rubber particles in a NaOH solution. Despite the potential benefits of this treatment, accurately estimating the CS value of NaOH-pretreated CRC remains challenging. To address this issue, a comprehensive database encompassing 118 entries on the fundamental mixtures of CRC along with NaOH concentration and pretreatment duration has been meticulously compiled for machine learning analysis. The random forest (RF) algorithm is employed to predict the 28-day CS value of NaOH-pretreated CRC. The model hyperparameters are optimized using a random search technique with 10-fold cross-validation. The findings reveal that the optimized RF attains acceptable predictive performance, yielding RMSE, MAE, and R2 values of 3.83 MPa, 2.84 MPa, and 0.85, respectively, on the testing dataset. Additionally, the model is interpreted using multiple techniques, including permutation importance, RF model-based feature importance, and Shapley additive explanation from global or local perspectives. The feature importance analyses consistently highlight the crucial role of crumb rubber content in determining the 28-day CS value of NaOH-pretreated CRC, and the influence of NaOH concentration and pretreatment time appear relatively inconsequential compared to features associated with the CRC mixture. This research contributes to a deeper understanding and better mixture design of CS for NaOH-pretreated CRC.","PeriodicalId":20860,"journal":{"name":"Progress in Rubber Plastics and Recycling Technology","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135870263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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