Polymer最新文献_第7页

The studies of structural characteristic improvement of pyrolysis carbon black by synchrotron radiation X-ray nano-computed tomography

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-02-15 DOI: 10.1016/j.polymer.2025.128157

Keran Zhu , Wei Jiang , Yuting Wang , Huasheng Yuan , Li Xia , Yesheng Zhu , Liang Chen

Pyrolysis carbon black (CBp) from waste tires not only has significant economic benefits but also addresses the urgent environmental problem of waste tire disposal. To date, many studies have been conducted to improve the properties of CBp in order to enhance its reinforcing effects. However, due to the structural complexity of CBp, it is crucial to quantitatively evaluate its structural discrepancies and identify the subtle distinctions between CBp and commercial carbon black (CB) in order to guide the improvement of CBp's properties. In this study, synchrotron radiation X-ray Nano-CT, X-ray photoelectron spectroscopy (XPS), and X-ray absorption spectroscopy (XAS) were employed to carefully investigate the spatial and chemical structures of CBp before and after nitric acid (HNO₃) treatment. We believe the main reasons for the low structurer (fractal dimension: 2.162 for CBp, lower than 2.307 for commercial CB), inhomogeneous size distributions, and inert chemical surface properties of CBp are the presence of rubber residues (volume ratio: 3.6 %) and other oxides remaining on the surface. These substances block pores, cover the active sites for chemical groups, and cause smaller particles to adhere to larger ones. After the residues were removed through HNO₃ treatment, the spatial and chemical structures of CBp were significantly improved (pore volume ratio increased from 2.7 % to 6.5 %), bringing its properties closer to those of commercial CB. The aim of this study is to identify subtle microstructural changes that can guide the optimization of conditions for producing CBp with the potential to replace commercial CB in tire fabrication.

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引用次数: 0

Influence of temperature and orientation on the mechanical properties of amorphous regions on the example of polyethylene

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-02-15 DOI: 10.1016/j.polymer.2025.128161

Artur Rozanski

In this work, the influence of temperature and molecular orientation on the elastic modulus of the amorphous regions (E_a) of semicrystalline polymers was determined using high-density polyethylene (HDPE) as an example. The decrease in E_a with increasing temperature was observed due to the gradual increase in the mobility of polymer chains, stimulated by the α relaxation processes within the crystalline regions. Thus, with the temperature increase, a gradual minimization of the “stiffening” influence of the crystals on the interlamellar layers was observed. Then, the influence of both the orientation and the undisturbed length of crystallites, as well as the orientation of the amorphous component, on the E_a value was demonstrated using materials deformed in a channel die with different compression ratios. At low compression ratios, a significant decrease in E_a was observed, stimulated by the fragmentation of lamellar crystals in the absence of measurable molecular orientation. At higher compression ratios, although the processes of crystal fragmentation remain active, a gradual increase in the orientation of chains in both the crystalline and amorphous components along the E_a measurement direction stimulated a significant increase in the E_a value. Consequently, E_a for the material with the highest compression ratio was six times higher compared to the reference material. The observed changes in E_a were also correlated with changes in the macroscopic Young's modulus.

本研究以高密度聚乙烯（HDPE）为例，测定了温度和分子取向对半结晶聚合物无定形区弹性模量（Ea）的影响。观察到 Ea 随温度升高而降低，这是由于聚合物链的流动性在结晶区内的 α 松弛过程的刺激下逐渐增加。因此，随着温度的升高，晶体对层间层的 "硬化 "影响逐渐减小。然后，使用在具有不同压缩比的槽模中变形的材料，证明了晶体的取向和未扰动长度以及无定形成分的取向对 Ea 值的影响。在低压缩比情况下，Ea 值会显著降低，这是由于在没有可测量的分子取向的情况下，片状晶体碎裂造成的。在较高的压缩比下，虽然晶体破碎过程仍然活跃，但沿 Ea 测量方向晶体和无定形成分链的取向逐渐增加，促使 Ea 值显著增加。因此，压缩比最高的材料的 Ea 值是参考材料的六倍。观察到的 Ea 变化也与宏观杨氏模量的变化相关。

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引用次数: 0

Pressure-resistant polyimide hollow fiber membranes for high-performance helium recovery from natural gas

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-02-14 DOI: 10.1016/j.polymer.2025.128164

Zhenyuan Li , Xing Liu , Ying Sun , Lili Gong , Chunfa Liao , Shuangjiang Luo

Industrial gas separation processes demand membranes with superior separation performance under high feed pressures. Herein, we fabricate defect-free hollow fiber membranes (HFMs) using 6FDA-mPDA_0.9-TFMB_0.1 copolyimide, achieving both exceptional pressure resistance and excellent gas separation performance. Through a dry-jet/wet-quench spinning approach, we systematically optimize the microstructure of the HFMs by adjusting the dope composition and spinning conditions. The results reveal that polymer concentration, dope-to-bore fluid ratio, and take-up rate have a significant impact on the pressure resistance of HFMs. Under optimized conditions, the fabricated HFMs exhibit a high burst pressure of 10.5 MPa, along with excellent gas separation performance, including a He permeance of 72.1 GPU and a He/CH₄ selectivity of 178. Additionally, mixed-gas permeation experiments conducted at feed pressures up to 750 PSIA demonstrate excellent resistance to heavy hydrocarbons. These ultra-strong, high-performance HFMs show great potential for efficient helium separation from natural gas under high-pressure conditions.

工业气体分离过程需要在高进料压力下具有卓越分离性能的膜。在本文中，我们使用 6FDA-mPDA0.9-TFMB0.1 共聚亚胺制造了无缺陷中空纤维膜 (HFM)，实现了优异的耐压性能和卓越的气体分离性能。我们采用干喷射/湿淬火纺丝方法，通过调整涂料成分和纺丝条件，系统地优化了中空纤维膜的微观结构。研究结果表明，聚合物浓度、掺杂剂与孔内流体的比例以及收率对高频膜的耐压性能有显著影响。在优化条件下，制造出的高频膜具有 10.5 兆帕的高爆破压力和优异的气体分离性能，包括 72.1 GPU 的 He 渗透率和 178 的 He/CH4 选择性。此外，在进料压力高达 750 PSIA 的条件下进行的混合气体渗透实验也证明了其对重烃的出色耐受性。这些超强、高性能的 HFM 显示出在高压条件下从天然气中高效分离氦气的巨大潜力。

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引用次数: 0

Cyclo-linear synthesis of amino silicone oil and study on the catalytic polymerization mechanism of phosphazene base 氨基硅油的环状线性合成及膦氮基催化聚合机理研究

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-02-13 DOI: 10.1016/j.polymer.2025.128163

Naifan Dong , Jintang Duan , Cailiang Zhang , Xueping Gu , Lianfang Feng , Liu Liu

Polysiloxanes with amino functional groups exhibit remarkable backbone flexibility, lubricity, and softness, positioning them a promising class of polymer materials. The phosphazene base (Bu-t-P₄) serves as an effective catalyst for the ring-opening copolymerization (ROCP) of octamethylcyclotetrasiloxane (D₄) and N-β-(aminoethyl)-γ-aminopropylmethyldiethoxysilane (KH-602). Under catalysis by 100 ppm of Bu-t-P₄ at 110 °C for 1 h, high yield of 93.59 % was achieved, resulting in amino silicone oil with a number-average molecular weight of 4.3 × 10³ g/mol, and a narrow molecular weight distribution (2.00). Fourier-transform infrared spectroscopy and nuclear magnetic resonance (NMR) confirmed that the product's structure corresponds to expected chemical shifts. In situ Raman spectroscopy monitoring and NMR analysis was employed to propose and validate the polymerization mechanism within the Bu-t-P₄-catalyzed system involving both cyclic and linear monomers. This study demonstrates an effective strategy, affirming that Bu-t-P₄ can be used as an efficient organic catalyst for the modified polysiloxanes.

带有氨基官能团的聚硅氧烷具有出色的骨架柔韧性、润滑性和柔软性，是一类前景广阔的聚合物材料。膦基（Bu-t-P4）是八甲基环四硅氧烷（D4）和 N-β-（氨基乙基）-γ-氨基丙基甲基二乙氧基硅烷（KH-602）开环共聚（ROCP）的有效催化剂。在 100 ppm 的 Bu-t-P4 催化下，于 110 ℃ 下反应 1 小时，获得了 93.59% 的高产率，得到的氨基硅油的数均分子量为 4.3×103 g/mol，分子量分布较窄（2.00）。傅立叶变换红外光谱和核磁共振（NMR）证实，该产品的结构符合预期的化学位移。利用原位拉曼光谱监测和核磁共振分析，提出并验证了在 Bu-t-P4 催化体系中涉及环状和线性单体的聚合机理。这项研究展示了一种有效的策略，证明 Bu-t-P4 可用作改性聚硅氧烷的高效有机催化剂。

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引用次数: 0

Comprehensive study of the steam-aging degradation behaviors and its correspondence to aging mechanism of PET monofilaments under artificially accelerated environment

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-02-12 DOI: 10.1016/j.polymer.2025.128159

Yingliang Zhang , Chenjun Liu , Kang Chen , Jiake Fan , Zhongli Zhang , Bohao Li , Yunsheng Xu , Xianming Zhang

Polyethylene terephthalate (PET) monofilament is extensively utilized in various industries due to its exceptional properties. However, PET monofilament is apt to hydrolysis when exposed to moisture and heat, and the corresponding steam-aging mechanism is not clearly, which severely affects its properties and service life. Hence, the pure PET and modified anti-hydrolysis PET monofilament by introducing hydrolysis stabilizers (polycarbodiimide, PCDI) were subjected to the pressure cooker test, and the resultant changes in mechanical properties were studied. Additionally, the varying length scales structural changes were compared to assess the effectiveness of the hydrolysis stabilizers and to reveal the steam-aging mechanisms of PET monofilaments. The results indicated that both PET monofilaments underwent three distinct aging processes, including pre-aging, steady-aging stage, and rapid failure aging stage. The disorientation of the molecular chain within the oriented amorphous region occurred in the pre-aging stage, giving rise to a subtle increment in breaking strain. Competitive recrystallization and hydrolysis reactions then took place simultaneously in the amorphous region, with the generation of small crystals acting as cross-linking points during the steady-aging stage, forming a more stable lamellar structure that delayed mechanical property loss due to hydrolysis-induced molecular chain breakage. The hydrolysis degradation reaction predominates in the rapid failure aging stage, resulting in a significant decrease in intrinsic viscosity, breaking stress and strain, and causing macroscopic defects. The degradation of molecular chains and the morphology damage induced by steam-aging are the main reasons for the decline of mechanical properties. Moreover, the addition of hydrolysis stabilizers (PCDI) predominantly influenced the molecular chain arrangement in the amorphous region, effectively prolonging the duration of the steady-aging stage and enhancing resistance to hydrolytic degradation conversely.

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引用次数: 0

Time and temperature-dependent fracture mechanics of self-healing vitrimers

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-02-12 DOI: 10.1016/j.polymer.2025.128148

Omar El Arwadi , Ajinkya Raut , Jacob L. Meyer , Andreas Polycarpou , Mohammad Naraghi

This study investigates the formation of exchangeable bonds and recovery of load bearing in bulk vitrimers. The critical load required to fracture compact tension samples in bulk aromatic thermosetting co-polyester (ATSP) and the ability of the material to heal the crack was studied as a function of duration and temperature of healing, and number of cycles. We established a marked improvement in healing efficiency at higher temperature especially in the first healing cycle, as the thermal energy reduces the energy barriers for bond re-formation. However, the healing efficiency progressively dropped in four healing cycles, and the drop was more significant at higher temperatures. We analyzed the cure kinetics of the ATSP by means of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and gel fraction tests. The results showed a particularly good thermal stability below 300 °C. The material loss from gel fraction tests was bound to 0.7 %. While not significant by mass, this mass will turn into volatile species and gas form, occupying a much larger volume, leading to formation of voids which serve as physical barrier to curing (material degredation). This is also evidenced in the increase in the fracture surface roughness, as improper bond exchange lead to the formation of volatile species. The formation of volatile species leads to surface asperities, reducing the contact area between the two faces of the crack, and results in a reduction in healing efficiency. The study concludes by outlining the differences between the intrinsic healing in vitrimers with high vitrification temperature and thermoplastics, highlighting the differences between the molecular mechanisms at play.

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引用次数: 0

Preparation and characterization of silk fibroin-sericin composite material through a one-pot method

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-02-11 DOI: 10.1016/j.polymer.2025.128149

Xin Luo , Yue Ma , Yanlei Hu , Huazhong Ma , Juan Yu , Liang Liu , Meijuan Chen , Yimin Fan

This study focused on the fabrication of a composite material composed of silk fibroin (SF) and sericin (SS). The "one-pot" method was proposed, directly introducing the two components into a formic acid-calcium chloride system to create gel-like material that possesses an abundance of porous structures and remarkable mechanical properties and toughness. By using a solvent exchange and evaporation technique, composite films were produced with outstanding tensile toughness even under wet conditions. Moreover, the influence of the formic acid-calcium chloride dissolution system on sericin and the composite material was investigated. Overall, this study provided a novel and effective approach to produce composite materials with desirable properties by using silk fibroin and sericin. It also highlighted the crucial role of both the formic acid-calcium chloride dissolution system and ethanol-water gradient treatment in the fabrication process. This research has implications for the development of new materials with potential applications in the fields of medicine, biotechnology, and tissue engineering.

{"title":"Preparation and characterization of silk fibroin-sericin composite material through a one-pot method","authors":"Xin Luo , Yue Ma , Yanlei Hu , Huazhong Ma , Juan Yu , Liang Liu , Meijuan Chen , Yimin Fan","doi":"10.1016/j.polymer.2025.128149","DOIUrl":"10.1016/j.polymer.2025.128149","url":null,"abstract":"<div><div>This study focused on the fabrication of a composite material composed of silk fibroin (SF) and sericin (SS). The \"one-pot\" method was proposed, directly introducing the two components into a formic acid-calcium chloride system to create gel-like material that possesses an abundance of porous structures and remarkable mechanical properties and toughness. By using a solvent exchange and evaporation technique, composite films were produced with outstanding tensile toughness even under wet conditions. Moreover, the influence of the formic acid-calcium chloride dissolution system on sericin and the composite material was investigated. Overall, this study provided a novel and effective approach to produce composite materials with desirable properties by using silk fibroin and sericin. It also highlighted the crucial role of both the formic acid-calcium chloride dissolution system and ethanol-water gradient treatment in the fabrication process. This research has implications for the development of new materials with potential applications in the fields of medicine, biotechnology, and tissue engineering.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"322 ","pages":"Article 128149"},"PeriodicalIF":4.1,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143393543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High-sensitivity piezoresistive sensors based on functionalized carbon nanotube/TPU composite for human motion detection

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-02-11 DOI: 10.1016/j.polymer.2025.128156

Ningjing Bai , Xuelong Chen , Huixin Wang , Caiyan Zhang , Jingbo Zhu , Wei Wang , Chenlong Kang , Youmao Tang , Zewen Li , Baozheng Cui , Haijun Niu , Zhe Wang

Piezoresistive sensors are widely used in a variety of fields due to their high sensitivity, low cost, and ease of integration. As technology advances, new materials and structures are designed to continue driving the improvement of piezoresistive sensor performance and the expansion of their fields of application. A unique functionalized multi-walled carbon nanotube (MWNTs-g-TPU) with thermoplastic polyurethane (TPU) chains was prepared by chemical grafting in this study. Conductive composites with piezoresistive properties were prepared by the solution blending method with TPU as the polymer matrix and MWNTs-g-TPU as the reinforcing filler. MWNTs-g-TPU interacts more strongly with TPU than non-functionalized MWNTs, significantly improving the mechanical, electrical, and piezoresistive properties of MWNTs-g-TPU/TPU composites. A sensor was fabricated using a 5.0 wt% MWNTs-g-TPU/TPU composite, demonstrating high sensitivity to external pressure. The composite material exhibited a stable piezoresistive response after multiple cycles, which indicates its great potential in the piezoresistive sensor field.

{"title":"High-sensitivity piezoresistive sensors based on functionalized carbon nanotube/TPU composite for human motion detection","authors":"Ningjing Bai , Xuelong Chen , Huixin Wang , Caiyan Zhang , Jingbo Zhu , Wei Wang , Chenlong Kang , Youmao Tang , Zewen Li , Baozheng Cui , Haijun Niu , Zhe Wang","doi":"10.1016/j.polymer.2025.128156","DOIUrl":"10.1016/j.polymer.2025.128156","url":null,"abstract":"<div><div>Piezoresistive sensors are widely used in a variety of fields due to their high sensitivity, low cost, and ease of integration. As technology advances, new materials and structures are designed to continue driving the improvement of piezoresistive sensor performance and the expansion of their fields of application. A unique functionalized multi-walled carbon nanotube (MWNTs-g-TPU) with thermoplastic polyurethane (TPU) chains was prepared by chemical grafting in this study. Conductive composites with piezoresistive properties were prepared by the solution blending method with TPU as the polymer matrix and MWNTs-g-TPU as the reinforcing filler. MWNTs-g-TPU interacts more strongly with TPU than non-functionalized MWNTs, significantly improving the mechanical, electrical, and piezoresistive properties of MWNTs-g-TPU/TPU composites. A sensor was fabricated using a 5.0 wt% MWNTs-g-TPU/TPU composite, demonstrating high sensitivity to external pressure. The composite material exhibited a stable piezoresistive response after multiple cycles, which indicates its great potential in the piezoresistive sensor field.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"322 ","pages":"Article 128156"},"PeriodicalIF":4.1,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143385596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of coal gasification fine slag's particle size on the processing properties of styrene butadiene rubber and natural rubber composites for replacing commercial silica

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-02-11 DOI: 10.1016/j.polymer.2025.128160

You Xu , Tong Zheng , Gongbao Guo , Jiahang Li , Hanjing Luo , Haosong Jiang , Weidong Ai , Yue Li , Cundi Wei

As a by-product of coal chemical industry, highly-discharged coal gasification fine slag has caused environmental problems such as land occupation and dust pollution. In this work, a high-ash coal gasification fine slag (AFS) and its ball milling products were selected to replace commercial precipitated silica (P-silica) and Micro-silica (M-silica) to fill Styrene-butadiene rubber (SBR) and Natural rubber (NR), respectively. The results showed that the filler network type of SBR changed from Particle Direct Contact Network (PDCN) to Rubber Shell Contact Network (RSCN) due to the replacement of P-silica by AFS fillers and the vulcanization speed improved. However, the replacement of M-silica by AFS-filler didn't change the filler network type of NR composites and resulted in a decrease of vulcanization speed. In both SBR and NR composites, the vulcanization speed, tensile strength, and activation energy of rubber molecular chain movement increased with the decrease of AFS-filler's particle size, which indicates that the reduction of AFS-filler's particle size is beneficial to the improvement of vulcanization speed and reinforcement. In addition, the T₉₀ of SBR filled with AFS fillers at 5 phr substitution was reduced by 29.0 %–43.3 % and the tensile strength was increased by 4.6 %–44.6 % compared to pure P-silica filled SBR. More importantly, the substitution of commercial silica by AFS reduces energy consumption in the rubber industry and opens up new ideas for improving the universality of coal gasification fine slag as rubber fillers.

{"title":"Effect of coal gasification fine slag's particle size on the processing properties of styrene butadiene rubber and natural rubber composites for replacing commercial silica","authors":"You Xu , Tong Zheng , Gongbao Guo , Jiahang Li , Hanjing Luo , Haosong Jiang , Weidong Ai , Yue Li , Cundi Wei","doi":"10.1016/j.polymer.2025.128160","DOIUrl":"10.1016/j.polymer.2025.128160","url":null,"abstract":"<div><div>As a by-product of coal chemical industry, highly-discharged coal gasification fine slag has caused environmental problems such as land occupation and dust pollution. In this work, a high-ash coal gasification fine slag (AFS) and its ball milling products were selected to replace commercial precipitated silica (P-silica) and Micro-silica (M-silica) to fill Styrene-butadiene rubber (SBR) and Natural rubber (NR), respectively. The results showed that the filler network type of SBR changed from Particle Direct Contact Network (PDCN) to Rubber Shell Contact Network (RSCN) due to the replacement of P-silica by AFS fillers and the vulcanization speed improved. However, the replacement of M-silica by AFS-filler didn't change the filler network type of NR composites and resulted in a decrease of vulcanization speed. In both SBR and NR composites, the vulcanization speed, tensile strength, and activation energy of rubber molecular chain movement increased with the decrease of AFS-filler's particle size, which indicates that the reduction of AFS-filler's particle size is beneficial to the improvement of vulcanization speed and reinforcement. In addition, the T<sub>90</sub> of SBR filled with AFS fillers at 5 phr substitution was reduced by 29.0 %–43.3 % and the tensile strength was increased by 4.6 %–44.6 % compared to pure P-silica filled SBR. More importantly, the substitution of commercial silica by AFS reduces energy consumption in the rubber industry and opens up new ideas for improving the universality of coal gasification fine slag as rubber fillers.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"322 ","pages":"Article 128160"},"PeriodicalIF":4.1,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143393318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

High-refractive-index ethylene/cyclic olefin/octene terpolymers with high optical transparency

IF 4.1 2区化学 Q2 POLYMER SCIENCE

Polymer

Pub Date : 2025-02-10 DOI: 10.1016/j.polymer.2025.128147

Yihua Zhao , Lei Cui , Yixin Zhang , Zhongbao Jian

Cyclic olefin copolymer is one of the most promising optical materials, but suffers from the issue of relatively low refractive index. The incorporation of 1-olefin into the polymer chain markedly enhanced its flexibility and solubility, and the elongation at break showed a corresponding rise, although the tensile strength underwent a decrease. In this contribution, the flexible 1-octene as the third comonomer was introduced to conduct the terpolymerization with ethylene and cyclic olefins by using the zirconocene catalyst under the activation of methylaluminoxane. The microstructures of the resultant terpolymers were characterized, and the effect of the incorporated 1-octene was determined by analyzing the optical, thermal and mechanical properties of the terpolymers. By introducing 1-octene, the glass transition temperatures (T_g) were lowered to the range of 63–184 °C, close to those (65–178 °C) of commercial materials. Moreover, these terpolymers exhibited high refractive indices (1.627–1.675 at 589 nm) and excellent optical transparency (up to 96 % at 400 nm). A high tensile strength of 52.0 MPa was achieved, along with a strain at break value of ε = 5.0 %. This strategy effectively reduced the T_g of cyclic olefin copolymers, promoting the possibility of processing at lower temperatures. More importantly, optical and mechanical properties were maintained. The developed terpolymers are particularly promising for applications in optical devices, such as high-performance lenses and advanced display technologies.

{"title":"High-refractive-index ethylene/cyclic olefin/octene terpolymers with high optical transparency","authors":"Yihua Zhao , Lei Cui , Yixin Zhang , Zhongbao Jian","doi":"10.1016/j.polymer.2025.128147","DOIUrl":"10.1016/j.polymer.2025.128147","url":null,"abstract":"<div><div>Cyclic olefin copolymer is one of the most promising optical materials, but suffers from the issue of relatively low refractive index. The incorporation of 1-olefin into the polymer chain markedly enhanced its flexibility and solubility, and the elongation at break showed a corresponding rise, although the tensile strength underwent a decrease. In this contribution, the flexible 1-octene as the third comonomer was introduced to conduct the terpolymerization with ethylene and cyclic olefins by using the zirconocene catalyst under the activation of methylaluminoxane. The microstructures of the resultant terpolymers were characterized, and the effect of the incorporated 1-octene was determined by analyzing the optical, thermal and mechanical properties of the terpolymers. By introducing 1-octene, the glass transition temperatures (<em>T</em><sub>g</sub>) were lowered to the range of 63–184 °C, close to those (65–178 °C) of commercial materials. Moreover, these terpolymers exhibited high refractive indices (1.627–1.675 at 589 nm) and excellent optical transparency (up to 96 % at 400 nm). A high tensile strength of 52.0 MPa was achieved, along with a strain at break value of <em>ε</em> = 5.0 %. This strategy effectively reduced the <em>T</em><sub>g</sub> of cyclic olefin copolymers, promoting the possibility of processing at lower temperatures. More importantly, optical and mechanical properties were maintained. The developed terpolymers are particularly promising for applications in optical devices, such as high-performance lenses and advanced display technologies.</div></div>","PeriodicalId":405,"journal":{"name":"Polymer","volume":"322 ","pages":"Article 128147"},"PeriodicalIF":4.1,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143385597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0