Pub Date : 2020-08-01DOI: 10.1177/2041247920960956
S. Zaim, O. Cherkaoui, H. Rchid, R. Nmila, R. El moznine
The rheological properties and spectrum infrared of polysaccharides extracted from Cystoseira myriophylloides algae were investigated in the concentrations range from 3 to 9% (w/v) and at different temperatures. Results of rheological characteristics in a steady shear rate showed pseudoplastic properties and the dynamic rheological properties showed a fluid-like viscoelastic behavior. The flow and viscoelastic characteristics of polysaccharides were described using the power-law (the Ostwald model). The values of flow behavior index of the sample were close to unity (0.91) for 3% and it decreased up to 0.71 for 9% revealing the shear-thinning (pseudoplastic) nature of these polysaccharides. Moreover, the consistency coefficient increased non-linearly with concentration and it was described by a power law. The flow behavior as a function of temperature was satisfactorily described using the Arrhenius law and the activation energy values were extracted. It decreased from 15.68 and 17.21 kJ/mol when the concentration increased from 5 to 9% (w/v). Additionally, in dynamic rheological measurements, tan δ > 1 and G″ > G′ reveling a shear-thinning behavior. Finally, the analysis of the FTIR spectra of these polysaccharides showed the presence of uronic acid groups. This behavior would suggest that polysaccharides extracted from Cystoseira myriophylloides could be an interesting additive as thickeners.
{"title":"Rheological investigations of water-soluble polysaccharides extracted from Moroccan seaweed Cystoseira myriophylloides algae","authors":"S. Zaim, O. Cherkaoui, H. Rchid, R. Nmila, R. El moznine","doi":"10.1177/2041247920960956","DOIUrl":"https://doi.org/10.1177/2041247920960956","url":null,"abstract":"The rheological properties and spectrum infrared of polysaccharides extracted from Cystoseira myriophylloides algae were investigated in the concentrations range from 3 to 9% (w/v) and at different temperatures. Results of rheological characteristics in a steady shear rate showed pseudoplastic properties and the dynamic rheological properties showed a fluid-like viscoelastic behavior. The flow and viscoelastic characteristics of polysaccharides were described using the power-law (the Ostwald model). The values of flow behavior index of the sample were close to unity (0.91) for 3% and it decreased up to 0.71 for 9% revealing the shear-thinning (pseudoplastic) nature of these polysaccharides. Moreover, the consistency coefficient increased non-linearly with concentration and it was described by a power law. The flow behavior as a function of temperature was satisfactorily described using the Arrhenius law and the activation energy values were extracted. It decreased from 15.68 and 17.21 kJ/mol when the concentration increased from 5 to 9% (w/v). Additionally, in dynamic rheological measurements, tan δ > 1 and G″ > G′ reveling a shear-thinning behavior. Finally, the analysis of the FTIR spectra of these polysaccharides showed the presence of uronic acid groups. This behavior would suggest that polysaccharides extracted from Cystoseira myriophylloides could be an interesting additive as thickeners.","PeriodicalId":20353,"journal":{"name":"Polymers from Renewable Resources","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/2041247920960956","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42471519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-08-01DOI: 10.1177/2041247920960974
Sorush Dovlatabadi
The combination of natural fibers in petroleum plastic soften industrial footprints on the environment. Plastic matrix can be filled with renewable resources leading to a greener composite that is biodegradable. This paper focuses on particulate kenaf filler modification and its affects on the properties of polypropylene, processing techniques and the use of particle size filler for improving linkages between fiber and polymeric matrixes.
{"title":"Effects of kenaf filler reinforcement on mechanical properties of molded polypropylene composites: A particle size study","authors":"Sorush Dovlatabadi","doi":"10.1177/2041247920960974","DOIUrl":"https://doi.org/10.1177/2041247920960974","url":null,"abstract":"The combination of natural fibers in petroleum plastic soften industrial footprints on the environment. Plastic matrix can be filled with renewable resources leading to a greener composite that is biodegradable. This paper focuses on particulate kenaf filler modification and its affects on the properties of polypropylene, processing techniques and the use of particle size filler for improving linkages between fiber and polymeric matrixes.","PeriodicalId":20353,"journal":{"name":"Polymers from Renewable Resources","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/2041247920960974","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42330802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-08-01DOI: 10.1177/2041247920960973
S. Rodriguez, F. Torres, Junior Arroyo, K. N. Gonzales, O. Troncoso, D. López
Novel carrageenan micro- and nanogels were developed via a sonication-assisted microemulsion processing route. The diameter of the dry samples ranged 197.3 −421.35 nm whereas the diameter of the samples suspended in water ranged 467.8–605.9 nm. Hybrid κ/ι-carrageenan, rather than κ- or ι-carrageenan was used for the first time for the preparation of micro- and nanogels. KCl was used as a cross-linking agent and Tween 80 was used as surfactant. The micro- and nanogels suspended in water were found to simultaneously exhibit a lower diameter, and a lower swelling ratio with higher Tween 80 content. The micro- and nanogel suspension yields a zeta potential value of −50.5 mV, superior to values reported elsewhere for pure κ- or ι-carrageenan micro- and nanogels. The high stability was attributed to the high hydrophile-lipophile balance (HLB = 15) value of Tween 80. These results suggest that hybrid κ/ι-carrageenan micro- and nanogels are promising candidates for smart therapeutics applications.
{"title":"Synthesis of highly stable κ/ι-hybrid carrageenan micro- and nanogels via a sonication-assisted microemulsion route","authors":"S. Rodriguez, F. Torres, Junior Arroyo, K. N. Gonzales, O. Troncoso, D. López","doi":"10.1177/2041247920960973","DOIUrl":"https://doi.org/10.1177/2041247920960973","url":null,"abstract":"Novel carrageenan micro- and nanogels were developed via a sonication-assisted microemulsion processing route. The diameter of the dry samples ranged 197.3 −421.35 nm whereas the diameter of the samples suspended in water ranged 467.8–605.9 nm. Hybrid κ/ι-carrageenan, rather than κ- or ι-carrageenan was used for the first time for the preparation of micro- and nanogels. KCl was used as a cross-linking agent and Tween 80 was used as surfactant. The micro- and nanogels suspended in water were found to simultaneously exhibit a lower diameter, and a lower swelling ratio with higher Tween 80 content. The micro- and nanogel suspension yields a zeta potential value of −50.5 mV, superior to values reported elsewhere for pure κ- or ι-carrageenan micro- and nanogels. The high stability was attributed to the high hydrophile-lipophile balance (HLB = 15) value of Tween 80. These results suggest that hybrid κ/ι-carrageenan micro- and nanogels are promising candidates for smart therapeutics applications.","PeriodicalId":20353,"journal":{"name":"Polymers from Renewable Resources","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/2041247920960973","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45126125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-02-01DOI: 10.1177/2041247920952653
N. Ykhlef, E. Lafranche
This paper aims to identify the main processing parameters that optimize as well the microcellular structure (cell size, cell density) of nitrogen (N2) foamed injection-moulded poly(butylene succinate) (PBS) as the resultant flexural properties of the part. The part beam geometry was designed so as to reproduce some geometrical shapes (e.g. thickness change, ribs, bosses or holes) occurring on most of industrial parts. A Taguchi L9 design of experiments (DOE) has been first used to quantify the effects of processing conditions on microcellular structure and mechanical performances. Among the processing parameters, the melt temperature, gas content, injection volumetric flow rate and back pressure were chosen for the DOE due to their level of influence on gas dissolution and nucleation phases. An analysis of variance (ANOVA) showed that the microcellular structure depended mainly on nitrogen content and, to a lesser extent, on back pressure representation of gas pressure saturation in the PBS/N2 system during the feeding stage. The resultant specific flexural properties were controlled by the skin/core ratio as well as the finesse of foam structure (cell sizes, cell density) but a 15% loss in specific performances was noted compared with the unfoamed part. The microcellular structure/mechanical performances could be thus established from the microstructure analysis. In a second step, the foamed microcellular structure has been improved by introduction of micro-talc in the PBS acting as cell nucleating agent (heterogeneous nucleation). A significant increase in cell density and cell reduction (40%) were observed.
{"title":"Injection-moulding of nitrogen-foamed bio-based microcellular poly(butylene succinate): Processing conditions/foam structure/flexural properties relationship","authors":"N. Ykhlef, E. Lafranche","doi":"10.1177/2041247920952653","DOIUrl":"https://doi.org/10.1177/2041247920952653","url":null,"abstract":"This paper aims to identify the main processing parameters that optimize as well the microcellular structure (cell size, cell density) of nitrogen (N2) foamed injection-moulded poly(butylene succinate) (PBS) as the resultant flexural properties of the part. The part beam geometry was designed so as to reproduce some geometrical shapes (e.g. thickness change, ribs, bosses or holes) occurring on most of industrial parts. A Taguchi L9 design of experiments (DOE) has been first used to quantify the effects of processing conditions on microcellular structure and mechanical performances. Among the processing parameters, the melt temperature, gas content, injection volumetric flow rate and back pressure were chosen for the DOE due to their level of influence on gas dissolution and nucleation phases. An analysis of variance (ANOVA) showed that the microcellular structure depended mainly on nitrogen content and, to a lesser extent, on back pressure representation of gas pressure saturation in the PBS/N2 system during the feeding stage. The resultant specific flexural properties were controlled by the skin/core ratio as well as the finesse of foam structure (cell sizes, cell density) but a 15% loss in specific performances was noted compared with the unfoamed part. The microcellular structure/mechanical performances could be thus established from the microstructure analysis. In a second step, the foamed microcellular structure has been improved by introduction of micro-talc in the PBS acting as cell nucleating agent (heterogeneous nucleation). A significant increase in cell density and cell reduction (40%) were observed.","PeriodicalId":20353,"journal":{"name":"Polymers from Renewable Resources","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/2041247920952653","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47613143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-02-01DOI: 10.1177/2041247920952649
H. Ostadi, Saeed Gilak Hakimabadi, F. Nabavi, M. Vossoughi, I. Alemzadeh
In this study, effects of glycerol (10, 20, and 30 wt%) and Sodium Montmorillonite (Na-MMT) (0%, 2.5%, and 5%) contents on the degradation of corn starch polymers were investigated. Films were prepared by casting corn starch solution using a modified method to enhance the nanoclay distribution. Biodegradability studies were performed by enzymatic and burial tests using pristine and enriched soils. The biodegradability of samples in pristine soil was faster, and all samples were fully degraded in 6 months. The effect of nanoparticles on the mass reduction in degradation was more pronounced than that of glycerol. In all glycerol concentrations, Na-MMT addition increased tensile strength. FTIR tests showed that degradability was related to glycerol leaching at first and then cleaving of α-1,4 bonds of starch, indicating the action of α-amylase produced by soil microorganisms. Good agreement between soil burial tests and enzymatic degradation was observed. An optimum Glycerol/Clay ratio was observed at which d-spacing and mechanical properties were maximum.
{"title":"Enzymatic and soil burial degradation of corn starch/glycerol/sodium montmorillonite nanocomposites","authors":"H. Ostadi, Saeed Gilak Hakimabadi, F. Nabavi, M. Vossoughi, I. Alemzadeh","doi":"10.1177/2041247920952649","DOIUrl":"https://doi.org/10.1177/2041247920952649","url":null,"abstract":"In this study, effects of glycerol (10, 20, and 30 wt%) and Sodium Montmorillonite (Na-MMT) (0%, 2.5%, and 5%) contents on the degradation of corn starch polymers were investigated. Films were prepared by casting corn starch solution using a modified method to enhance the nanoclay distribution. Biodegradability studies were performed by enzymatic and burial tests using pristine and enriched soils. The biodegradability of samples in pristine soil was faster, and all samples were fully degraded in 6 months. The effect of nanoparticles on the mass reduction in degradation was more pronounced than that of glycerol. In all glycerol concentrations, Na-MMT addition increased tensile strength. FTIR tests showed that degradability was related to glycerol leaching at first and then cleaving of α-1,4 bonds of starch, indicating the action of α-amylase produced by soil microorganisms. Good agreement between soil burial tests and enzymatic degradation was observed. An optimum Glycerol/Clay ratio was observed at which d-spacing and mechanical properties were maximum.","PeriodicalId":20353,"journal":{"name":"Polymers from Renewable Resources","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/2041247920952649","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42273521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-02-01DOI: 10.1177/2041247920952641
Cassiano MN Romagnolli, Gabriela P. Leite, Tiago Rodrigues, C. L. Morelli
Plastic packagings are widely used for several food products. Considering the relatively short service lifetime of this application, it is important to perceive in the search of eco-friendly alternatives to this market, such as polymers from renewable sources, as thermoplastic starch and “green” polyethylene. The incorporation of an antibacterial agent to the packaging can extend food shelf life. Camellia sinensis is a plant with known antibacterial properties used in the preparation of “green tea.” In the present work, green tea was incorporated to a blend of cassava thermoplastic starch and high-density polyethylene (HDPE) by melt extrusion, aiming application as active packaging. Films were obtained by thermopressing and characterized through infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and tensile tests. Their antibacterial properties were evaluated against Staphylococcus aureus and Escherichia coli. The results indicated that the material developed has potential for food packaging applications. Moreover, the methodology applied for green tea incorporation in the Starch/HDPE films can be extended for many extracts from natural components, contributing to the advancement of research in the development of active packaging for food products. To the best of our knowledge, no previous work studied the properties of starch/HDPE blend with green tea.
{"title":"Blend of cassava starch and high-density polyethylene with green tea for food packaging","authors":"Cassiano MN Romagnolli, Gabriela P. Leite, Tiago Rodrigues, C. L. Morelli","doi":"10.1177/2041247920952641","DOIUrl":"https://doi.org/10.1177/2041247920952641","url":null,"abstract":"Plastic packagings are widely used for several food products. Considering the relatively short service lifetime of this application, it is important to perceive in the search of eco-friendly alternatives to this market, such as polymers from renewable sources, as thermoplastic starch and “green” polyethylene. The incorporation of an antibacterial agent to the packaging can extend food shelf life. Camellia sinensis is a plant with known antibacterial properties used in the preparation of “green tea.” In the present work, green tea was incorporated to a blend of cassava thermoplastic starch and high-density polyethylene (HDPE) by melt extrusion, aiming application as active packaging. Films were obtained by thermopressing and characterized through infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and tensile tests. Their antibacterial properties were evaluated against Staphylococcus aureus and Escherichia coli. The results indicated that the material developed has potential for food packaging applications. Moreover, the methodology applied for green tea incorporation in the Starch/HDPE films can be extended for many extracts from natural components, contributing to the advancement of research in the development of active packaging for food products. To the best of our knowledge, no previous work studied the properties of starch/HDPE blend with green tea.","PeriodicalId":20353,"journal":{"name":"Polymers from Renewable Resources","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/2041247920952641","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44325417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-01DOI: 10.1177/2041247920952636
Wei Keat Ng, W. Chow, H. Ismail
Cellulose nanocrystals were extracted from agricultural waste corn cob using acid hydrolysis followed by freeze drying. Poly(lactic acid)/corn cob cellulose nanocrystals (PLA/CCNC) composites were prepared using solvent casting. The properties of CCNC were characterized using transmission electron microscope (TEM), zeta potential analyzer, and thermogravimetric analyzer (TGA). The effects of CCNC on the thermal properties of PLA were examined using differential scanning calorimetry (DSC) and TGA. From the SEM and TEM results, the irregular shaped and micron-sized corn cob powder was transformed to needle-like shaped nanocellulose (aspect ratio approximately 30.80) after the acid hydrolysis process. TGA results show that the thermal stability of CCNC is higher than that of corn cob powder. The zeta potential of CCNC is −24.6 mV, which indicates there is a repulsion force between the individual CCNC and making them disperse uniformly and stable in aqueous media. DSC and TGA results show that the crystallinity and thermal stability of PLA were increased by the incorporation of CCNC. This demonstrates that the CCNC is a potential bio-nanofiller with good thermal stability and nucleating-ability for PLA.
{"title":"Thermal properties enhancement of poly(lactic acid) by corn cob cellulose nanocrystals","authors":"Wei Keat Ng, W. Chow, H. Ismail","doi":"10.1177/2041247920952636","DOIUrl":"https://doi.org/10.1177/2041247920952636","url":null,"abstract":"Cellulose nanocrystals were extracted from agricultural waste corn cob using acid hydrolysis followed by freeze drying. Poly(lactic acid)/corn cob cellulose nanocrystals (PLA/CCNC) composites were prepared using solvent casting. The properties of CCNC were characterized using transmission electron microscope (TEM), zeta potential analyzer, and thermogravimetric analyzer (TGA). The effects of CCNC on the thermal properties of PLA were examined using differential scanning calorimetry (DSC) and TGA. From the SEM and TEM results, the irregular shaped and micron-sized corn cob powder was transformed to needle-like shaped nanocellulose (aspect ratio approximately 30.80) after the acid hydrolysis process. TGA results show that the thermal stability of CCNC is higher than that of corn cob powder. The zeta potential of CCNC is −24.6 mV, which indicates there is a repulsion force between the individual CCNC and making them disperse uniformly and stable in aqueous media. DSC and TGA results show that the crystallinity and thermal stability of PLA were increased by the incorporation of CCNC. This demonstrates that the CCNC is a potential bio-nanofiller with good thermal stability and nucleating-ability for PLA.","PeriodicalId":20353,"journal":{"name":"Polymers from Renewable Resources","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/2041247920952636","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44324545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-01DOI: 10.1177/2041247920952644
Sashivinay Kumar Gaddam, A. Palanisamy
A novel cottonseed oil-based ionizable polyol was introduced as ionic soft segment in waterborne polyurethane dispersion (PUD) synthesis. The ionizable polyol was synthesized by ring opening of epoxidized cottonseed oil (ECSO) with 4-aminobenzoic acid (PABA) and blended with hydroxylated cottonseed oil polyol (HCSO) in different weight ratios to develop a series of mixed polyols having different hydroxyl numbers viz., 146, 130 and 114 mg KOH/g. Three different PUDs were synthesized using the mixed polyols, isophorone diisocyanate, and 3-aminopropyltriethoxysilane. The chemical structure, thermo-mechanical properties, and surface properties of cured PUD films were examined using Fourier-transform infrared spectroscopy (FTIR), Dynamic mechanical thermal analysis (DMTA), universal testing machine (UTM) and contact angle measurements respectively. The effect of Si–O–Si cross-linking network density, which increases with an increase in OH values of the mixed polyol was also investigated. All the PUDs prepared in this study exhibited good storage stability (>4 months), and the average particle sizes of PUDs ranged from 18 to 124 nm. The highest hydroxyl mixed polyol derived PUD film (PUD-35 film) exhibited high thermal stability, mechanical strength; Tg value, water contact angle value, chemical, and abrasion resistance properties due to the extended siloxane cross-link network structure. The introduction of ionizable polyol into the soft segment led to an improvement in hard and soft segment phase mixing of PUDs, and this strategy could enrich the exploration of new synthetic methodologies in the field of bio-based PUD manufacturing.
{"title":"Ionizable polyol from cottonseed oil for anionic waterborne polyurethane-silanol dispersions","authors":"Sashivinay Kumar Gaddam, A. Palanisamy","doi":"10.1177/2041247920952644","DOIUrl":"https://doi.org/10.1177/2041247920952644","url":null,"abstract":"A novel cottonseed oil-based ionizable polyol was introduced as ionic soft segment in waterborne polyurethane dispersion (PUD) synthesis. The ionizable polyol was synthesized by ring opening of epoxidized cottonseed oil (ECSO) with 4-aminobenzoic acid (PABA) and blended with hydroxylated cottonseed oil polyol (HCSO) in different weight ratios to develop a series of mixed polyols having different hydroxyl numbers viz., 146, 130 and 114 mg KOH/g. Three different PUDs were synthesized using the mixed polyols, isophorone diisocyanate, and 3-aminopropyltriethoxysilane. The chemical structure, thermo-mechanical properties, and surface properties of cured PUD films were examined using Fourier-transform infrared spectroscopy (FTIR), Dynamic mechanical thermal analysis (DMTA), universal testing machine (UTM) and contact angle measurements respectively. The effect of Si–O–Si cross-linking network density, which increases with an increase in OH values of the mixed polyol was also investigated. All the PUDs prepared in this study exhibited good storage stability (>4 months), and the average particle sizes of PUDs ranged from 18 to 124 nm. The highest hydroxyl mixed polyol derived PUD film (PUD-35 film) exhibited high thermal stability, mechanical strength; Tg value, water contact angle value, chemical, and abrasion resistance properties due to the extended siloxane cross-link network structure. The introduction of ionizable polyol into the soft segment led to an improvement in hard and soft segment phase mixing of PUDs, and this strategy could enrich the exploration of new synthetic methodologies in the field of bio-based PUD manufacturing.","PeriodicalId":20353,"journal":{"name":"Polymers from Renewable Resources","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/2041247920952644","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48225793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-08-07DOI: 10.1177/2041247919863631
Lu Han, Fangwu Ma, Shixian Chen, Yongfeng Pu
The effect of basalt fiber (BF) content on the properties of BF-reinforced polylactic acid (PLA) composites was investigated. Composites with 10, 20, 30, 40, 50, and 60 wt% BF were fabricated. The results revealed that (1) the mechanical properties improved with increasing BF content. The maximum tensile strength and modulus of the composites (i.e. 140 and 5050 MPa, respectively) occurred at a BF content of 50%. The maximum flexural strength, that is, 159.5 MPa was two times larger than that of the pure PLA and was obtained at a BF content of 40%. However, the mechanical properties deteriorated at BF contents >50%. (2) BF can stop storage modulus loss and are effective in improving the crystallinity, as revealed by dynamic mechanical analysis and differential scanning calorimetry measurements. The crystallinity improved from 34.6% to 54.6% with BF addition. (3) After the accelerated aging test, pure PLA was too weak for testing. However, high values of the tensile modulus (i.e. 60% that of the nonaged samples) were maintained by the BF-reinforced PLA. This resulted possibly from the high crystallinity of the PLA composites. Therefore, suitable amounts of BF as reinforcements can yield improvements in the performance of PLA composites.
{"title":"Effect of short basalt fibers on durability, mechanical properties, and thermal properties of polylactic acid composites","authors":"Lu Han, Fangwu Ma, Shixian Chen, Yongfeng Pu","doi":"10.1177/2041247919863631","DOIUrl":"https://doi.org/10.1177/2041247919863631","url":null,"abstract":"The effect of basalt fiber (BF) content on the properties of BF-reinforced polylactic acid (PLA) composites was investigated. Composites with 10, 20, 30, 40, 50, and 60 wt% BF were fabricated. The results revealed that (1) the mechanical properties improved with increasing BF content. The maximum tensile strength and modulus of the composites (i.e. 140 and 5050 MPa, respectively) occurred at a BF content of 50%. The maximum flexural strength, that is, 159.5 MPa was two times larger than that of the pure PLA and was obtained at a BF content of 40%. However, the mechanical properties deteriorated at BF contents >50%. (2) BF can stop storage modulus loss and are effective in improving the crystallinity, as revealed by dynamic mechanical analysis and differential scanning calorimetry measurements. The crystallinity improved from 34.6% to 54.6% with BF addition. (3) After the accelerated aging test, pure PLA was too weak for testing. However, high values of the tensile modulus (i.e. 60% that of the nonaged samples) were maintained by the BF-reinforced PLA. This resulted possibly from the high crystallinity of the PLA composites. Therefore, suitable amounts of BF as reinforcements can yield improvements in the performance of PLA composites.","PeriodicalId":20353,"journal":{"name":"Polymers from Renewable Resources","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/2041247919863631","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43894170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-24DOI: 10.1177/2041247919863633
Z. Karami, M. Zohuriaan-Mehr, K. Kabiri, N. Ghasemi Rad
This study deals with the synthesis of vegetable oil (VO)-derived formulated resins with high bio-based content (30–77%) as potential renewable alternatives to conventional fossil-based vinyl ester (VE) and unsaturated polyester (UP) resins. First, epoxy acrylate was synthesized from a commercial epoxy resin via acrylation with acrylic acid. Then, acrylated epoxidized sesame oil (AESSO) and maleated castor oil (MCO) were synthesized and spectrally characterized. Afterward, networks of VE, AESSO, and MCO or their binary blends were prepared. The curing trend of the resins was investigated by differential scanning calorimetry. According to thermal and thermomechanical analysis, all of the VO-based networks possessed slightly inferior properties compared to those of VE. However, the adhesion strength of the VO-based alloying systems was higher than that of their petroleum-based counterpart based on T-peel and lap shear tests. Overall, it was concluded that the bio-resourced alloys could be considered as good alternatives to VE and UP resins, and the novel bio-resin formulations may be designed for adhesives, the polymer–matrix composites, and surface coating applications.
{"title":"Bio-based thermoset alloys from epoxy acrylate, sesame oil- and castor oil-derived resins: Renewable alternatives to vinyl ester and unsaturated polyester resins","authors":"Z. Karami, M. Zohuriaan-Mehr, K. Kabiri, N. Ghasemi Rad","doi":"10.1177/2041247919863633","DOIUrl":"https://doi.org/10.1177/2041247919863633","url":null,"abstract":"This study deals with the synthesis of vegetable oil (VO)-derived formulated resins with high bio-based content (30–77%) as potential renewable alternatives to conventional fossil-based vinyl ester (VE) and unsaturated polyester (UP) resins. First, epoxy acrylate was synthesized from a commercial epoxy resin via acrylation with acrylic acid. Then, acrylated epoxidized sesame oil (AESSO) and maleated castor oil (MCO) were synthesized and spectrally characterized. Afterward, networks of VE, AESSO, and MCO or their binary blends were prepared. The curing trend of the resins was investigated by differential scanning calorimetry. According to thermal and thermomechanical analysis, all of the VO-based networks possessed slightly inferior properties compared to those of VE. However, the adhesion strength of the VO-based alloying systems was higher than that of their petroleum-based counterpart based on T-peel and lap shear tests. Overall, it was concluded that the bio-resourced alloys could be considered as good alternatives to VE and UP resins, and the novel bio-resin formulations may be designed for adhesives, the polymer–matrix composites, and surface coating applications.","PeriodicalId":20353,"journal":{"name":"Polymers from Renewable Resources","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1177/2041247919863633","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47184684","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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