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Mechanical and Thermal Properties of Sugar Palm Fiber Reinforced thermoplastic polyurethane Composites:Effect of Silane Treatment and Fiber Loading

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Journal of Renewable Materials 2018年第5期6卷 477-492页

作者： A.Atiqah M.Jawaid S.M.Sapuan M.R.Ishak Laboratory of Biocomposite Technology Institute of Tropical Forestry and Forest Products(INTROP)Universiti Putra MalaysiaSerdang 43400SelangorMalaysia Department of Mechanical Engineering Universiti Putra MalaysiaSerdang 43400SelangorMalaysia Department of Aerospace Engineering Universiti Putra MalaysiaSerdang 43400SelangorMalaysia

The aim of the present study was to develop sugar palm fiber(SPF)reinforced thermoplastic polyurethane(TPU)composites and to investigate the effects of fiber surface modification by 2%silane treatment and fiber loading(0,10,20,30,40 and 50 wt%)on the mechanical and thermal properties of the obtained *** treatment was employed to improve the fiber-matrix interface,which was expected to boost the mechanical strength of the composites,in terms of tensile,flexural and impact *** properties were also investigated by thermal gravimetric analysis(TGA)and dynamic mechanical analysis(DMA)to assess the thermal stability of the developed ***,scanning electron microscopy(SEM)was used to study the tensile fracture samples of composites with a view towards evaluating the effects of fiber surface treatments on the fiber/matrix interfacial *** findings of this study reveal that the silane treatment has determined good bonding and linkage of the cellulose fiber to the TPU matrix,hence contributing to enhanced mechanical and thermal properties of the *** composite formulation with 40 wt%sugar palm fiber loading showed optimum values such as 17.22 MPa for tensile,13.96 MPa for flexural,and 15.47 kJ/m^2 for impact ***,the formulations with higher fiber content exhibited satisfactory values of storage modulus and thermal degradation,while their good interfacial adhesion was evidenced by SEM images.

关键词： Sugar palm fibers silane treatment thermoplastic polyurethane sugar palm fiber-reinforced composites mechanical properties thermo-mechanical properties

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Fabrication and Characterization of Poly(Styrene-Butadiene-Styrene)/thermoplastic polyurethane Blends

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Journal of Materials Science and Chemical Engineering 2021年第2期9卷 1-10页

作者： Yuhsin Tsai Mu-Chen Kuo Jyh-Horng Wu School of Chinese Medicine China Medical University Taiwan Department of Materials Engineering Kun Shan University Taiwan Division of Polymer Research Industrial Technology Research Institute Taiwan

This investigation presents thermoplastic elastomers (TPEs) based on poly (styrene-butadiene-styrene) (SBS) and thermoplastic polyurethane (TPU) materials were prepared with varying compositions. A series of works were conducted on the relationships between rheological, optical properties, morphology, mechanical properties, abrasion resistance and thermostability given. The results showed that the shear viscosity of SBS not obvious effect with TPU content. The optical properties of the SBS/TPU blend that its uniform transparency. The morphology characteristics indicating the phase diversion and the variation in the size of the SBS domains from large to small as the TPU contents increased, with heterogeneous domain dispersions. Additionally, the mechanical properties, abrasion resistance and thermal resistance are improved as the amount of added TPU is increased, suggesting that the blending of SBS with TPU is consistent with the compound rule.

关键词： thermoplastic Elastomers Poly(Styrene-Butadiene-Styrene) thermoplastic polyurethane

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Catalyst Control of Interfacial Welding Mechanical Properties of Vitrimers

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Chinese Journal of Polymer Science 2022年第6期40卷 611-617页

作者： Zong-Tang Lv Hong-Kun Yang Dong Wang State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

Interfacial welding of thermosetting polymers has been a challenge,but vitrimers with dynamic covalent networks open numerous opportunities for welding and adhesion of these *** this work,we performed interfacial welding between epoxy-based vitrimers and an epoxy vitrimer and a thermoplastic polyurethane(TPU).Catalyst-controlled interfacial mechanical properties for both the vitrimer/vitrimer and vitrimer/TPU are observed,that is,the more efficient the catalyst for the transesterification reactions,the larger the interfacial fracture energy is,and the better the welding strength will *** interfacial mechanical properties are also found to be independent of the original mechanical properties of the *** for a vitrimer with poor mechanical properties,both the welded vitrimer/vitrimer and vitrimer/TPU exhibit larger interfacial fracture energy than the one with better mechanical properties as long as the former uses more efficient catalyst.

关键词： Vitrimers Interfacial welding Epoxy Catalyst thermoplastic polyurethane

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Piezoresistive behavior of elastomer composites with segregated network of carbon nanostructures and alumina

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纳米材料科学:英文版 2023年第3期5卷 312-318页

作者： Chun-Yan Tang Lei Liu Kai Ke Bo Yin Ming-Bo Yang Wei Yang College of Polymer Science and Engineering Sichuan UniversityState Key Laboratory of Polymer Materials EngineeringChengdu610065SichuanChina

Electrically conductive elastomer composites(CECs)with segregated networks of conductive nanofillers show high potential in stretchable strain sensors due to balanced mechanical and electrical properties,yet the sensitivity at low strain is generally insufficient for practical ***,we report an easy and effective way to improve the resistive response to low strain for CECs with segregated network structure via adding stiff alumina into carbon nanostructures(CNS).The CEC containing 0.7 wt%CNS and 5 wt%Al_(2)O_(3) almost sustains the same elasticity(elongation at break of~900%)and conductivity(0.8 S/m)as the control,while the piezoresistive sensitivity is significantly *** polyurethane(TPU)composites with a segregated network of hybrid nanofillers(CNS and Al_(2)O_(3))show much higher strain sensitivity(Gauge factor,GF-566)at low strain(45%strain)due to a local stress concentration effect,this sensitivity is superior to that of TPU/CNS composites(GF-11).Such a local stress concentration effect depends on alumina content and its distribution at the TPU particle *** addition,CECs with hybrid fillers show better reproducibility in cyclic piezoresistive behavior testing than the *** work offers an easy method for fabricating CECs with a segregated filler network offering stretchable strain sensors with a high strain sensitivity.

关键词： thermoplastic polyurethane Carbon nanostructures Alumina Conductive elastomer composites Stretchable strain sensor

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Highly Stretchable and Conductive Hybrid Fibers for High-performance Fibrous Electrodes and All-solid-state Supercapacitors

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高分子科学：英文版 2020年第5期38卷 531-539,I0007页

作者： Gui-Qing Wu Xin-Yu Yang Jia-Hui Li Nan Sheng Cheng-Yi Hou Yao-Gang Li Hong-Zhi Wang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Materials Science and Engineering Nanyang Technological University639798Singapore

The development of lightweight,flexible,and stretchable energy storage systems is essential for state-of-the-art electronic *** propose a new and broad strategy to fabricate a stretchable and conductive GO/CNTs-TPU fiber electrode by direct wet spinning,from which a flexible fibrous supercapacitor is *** fibrous electrode exhibits a high strength of 11.68 MPa,high conductivity of 342 S/cm,and high specific capacitances(21.8 mF/cm,36.45 F/cm^3,and 95 F/g).The specific capacitance of the assembled all-solid-state hybrid fiber-shaped supercapacitor reaches 14.3 F/cm^*** 5000 charge-discharge cycles,97%of the capacitance of the hybrid supercapacitor is *** high-strength electrochemical electrode materials could be potential candidates for applications in practical and large-scale energy storage systems and textile clothes.

关键词： Graphene Carbon nanotubes thermoplastic polyurethane Supercapacitor Flexibility

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Effect of Polydimethylsilxoane Molecular of Soft Segment on Novel Urethane-Siloxane Copolymers

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Journal of Donghua University(English Edition) 2016年第1期33卷 38-45页

作者：杨凯戴泽亮董擎之 Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and Technology

Novel segmented urethane-siloxane copolymers were synthesized by a two-step bulk polymerization procedure using 4,4'-methylenediphenyl diisocyanate( MDI) and 1,4-butanediol( BDO)as the hard segment components and novel polypropyleneoxide polyether( PPO) blocked polydimethylsilxoane( PDMS) α,ω-dihydroxy-( PPO-PDMS-PPO) as the soft segment component,where the hard segment content was 30% by weight,and the molar ratio of NCO / OH was 1. 02. A series of urethane-siloxane copolymers were prepared from different molecular weights of α,ω-dihydroxy-( PPO-PDMS-PPO). The soft segments were different in the molecular of PDMS block segment. Chemical structure,morphology,mechanical properties,surface properties and thermal properties of thermoplastic polyurethane( TPU) were investigated by Fourier transform infrared spectroscopy( FT-IR),scanning electron microscopy and energy dispersive X-ray spectroscopy( SEM-EDX),mechanical properties( MP) test,water contact angle( WCA) test,differential scanning calorimetry( DSC),thermogravimetric analysis( TGA), respectively. According to the obtained results, the hydrophobicity of silicone modified TPU promoted,surface WCA increased from 73° to 120°. Low temperature resistant performance was improved,and the glass transition temperature decreased from- 44. 2℃ to- 120. 8℃. Thermal stability was also improved,the beginning temperature of thermal degradation increased from 281 ℃to 299 ℃.

关键词： α,ω-dihydroxy-(PPO-PDMS-PPO) thermoplastic polyurethane hydrophobicity low temperature resistant performance thermal stability

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人造血管用聚碳酸酯基聚氨酯弹性体的合成及其结构-性能研究

人造血管用聚碳酸酯基聚氨酯弹性体的合成及其结构-性能研究

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作者：覃一朗北京协和医学院

学位级别：硕士

心血管疾病是我国未来老龄化社会面临的主要医疗负担之一,人工替代植入物(比如人工血管、人工瓣膜等)是手术治疗方案中重要的高值耗材。人工血管目前主要采用膨体聚四氟乙烯(ePTFE)制备,人工瓣膜则主要以金属和牛/猪心包制备。其中,热... 详细信息

心血管疾病是我国未来老龄化社会面临的主要医疗负担之一,人工替代植入物(比如人工血管、人工瓣膜等)是手术治疗方案中重要的高值耗材。人工血管目前主要采用膨体聚四氟乙烯(ePTFE)制备,人工瓣膜则主要以金属和牛/猪心包制备。其中,热塑性聚氨酯(thermoplastic polyurethane,TPU)弹性体因其良好的生物相容性和力学性能而被广泛应用于制造血管补片、心脏起搏器导线、人工血管、人工心脏等,挽救了许多心血管病患者的生命。但是目前我国使用的医用TPU弹性体全部依赖国外进口产品,国内缺乏针对长期植入性医用TPU弹性体的自主生产能力。为研制国产化具有自主知识产权的医用级TPU弹性体,本论文第二章结合文献、专利和现有聚氨酯工业生产的经验,通过核磁共振氢谱(hydrogen nuclear magnetic resonance,HNMR)、红外光谱(Fourier transform infrared spectroscopy,FT-IR)、扫描电子显微镜(scanning electron microscope,SEM)研究了现有进口医用级TPU弹性体的化学结构和微观形貌,并使用动态机械力学分析(dynamic mechanical analysis,DMA)、原位小角X射线散射/广角X射线衍射(in situ small-angle X-ray scattering/wide-angle X-ray diffraction,in situ SAXS/WAXD)联用和工程应力应变拉伸测试对比植入羊体内24周前后聚氨酯人工血管的链结构、凝聚态结构和力学性能的变化及其短期抗生物降解性能。植入动物体内前后分子链未见断裂,表面无显著裂纹,TPU本体的力学性能无显著改变,证明进口 TPU产品在手术急性期良好的抗生物降解综合能力。为了实现国产医用TPU弹性体的替代进口和稳定化生产,本论文第三章和第四章通过一步法聚合得到了不同扩链剂(BDO、PDO、EO和MEA)的四个聚碳酸酯基TPU样品(系列Ⅰ)和四个不同硬段含量的样品(系列Ⅱ),使用红外光谱(FT-IR)、核磁共振氢谱(HNMR)、凝胶渗透色谱(gel permeation chromatography,GPC)、热重分析(thermogravimetric analysis,TGA)、差示扫描量热法(differential scanning calorimetry,DSC)、动态机械力学分析(DMA)、工程应力应变拉伸测试、扫描电子显微镜(SEM)、原子力显微镜(atomic force microscopy,AFM)、原位小角度X线散射(SAXS)和广角X射线衍射(WAXD)、体外细胞毒性和体外溶血试验对两个系列的样品化学结构、力学性能和生物相容性进行测试和评估。系列Ⅰ样品中,PCU-EO的FT-IR结果显示其晶区羰基氢键伸缩振动峰占比最大,PCU-PDO的不规则/无定形区羰基氢键占比最大,PCU-MEA的游离羰基伸缩振动信号峰面积占比最多。PCU-BDO的热稳定性最好,DMA分析显示PCU-MEA和PCU-BDO在37℃下的储能模量较高,PCU-MEA软段的玻璃化转变温度为-13.1℃。原位WAXD/SAXS结果表明PCU-EO的微相分离程度最高,PCU-PDO无相分离现象,四个样品在500%应变过程中皆保持无定形形态,未发生拉伸诱导结晶现象。PCU-MEA在系列一样品中拉伸强度最高,达到57.8±4.0 MPa,PCU-BDO的断裂伸长率最大,达到1203.3±62.9%。BDO与MEA在四种扩链剂中对材料的力学性能的改善能力较好。系列Ⅱ样品的DSC结果显示其均为无定形态,PCU-36在100-280℃热稳定性最好,DMA测得其软段Tg为-5.82℃,拉伸强度在系列Ⅱ样品中为最高,达到54.2±6.7 MPa。硬段含量在32%-36%的样品,其综合力学性能较理想。两个系列的样品细胞毒性测试结果均提示具有细胞毒性,而使用低剂量有机锡催化剂合成得到的样品则不具有细胞毒性,初步考虑样品的毒性最可能来源于较高的催化剂用量。第二系列样品中,PCU-32和PCU-36两个材料通过了体外溶血试验,初步证明其具有良好的血液相容性。通过将两个自合成系列样品同进口样品进行对照与分析,我们自合成了以BDO和MEA两种混合扩链剂的PCU材料,两种材料在结构、力学性能上与进口样品相当,初步应用结果显示,其在医用领域,尤其是长期植入和血液接触类心血管高值耗材的生产中具有较好的应用前景。

关键词： thermoplastic polyurethane Vascular Graft(artificial blood vessel) Structure-Mechanical Property Relationship Biocompatibility Domestic Substitute

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聚氯乙烯高性能化、抗静电功能化研究

聚氯乙烯高性能化、抗静电功能化研究

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2014年全国高分子材料科学与工程研讨会

作者：李侃社汪晓芹牛红梅李锦闫兰英陈创前康洁梁耀东朱雪丹西安科技大学化学与化工学院高分子研究所

我国是聚氯乙烯(PVC)第一生产和应用大国,截至2013年底,截至2013年底,产能、产量分别达到2476万吨和1530万吨。PVC因其难燃、耐磨、抗化学腐蚀、气体水汽低渗透、综合机械性能优良、制品透明、电绝缘、隔热隔音而得到广泛应用。但聚氯... 详细信息

我国是聚氯乙烯(PVC)第一生产和应用大国,截至2013年底,截至2013年底,产能、产量分别达到2476万吨和1530万吨。PVC因其难燃、耐磨、抗化学腐蚀、气体水汽低渗透、综合机械性能优良、制品透明、电绝缘、隔热隔音而得到广泛应用。但聚氯乙烯材料存在明显的缺陷:抗冲击性能差,热稳定性差,难加工,这大大制约了PVC材料应用的范围。为了改善PVC性能方面存在的不足或赋予新的功能,拓宽PVC的应用范围。国内外学者

关键词： PVC Strengthening and toughening Kaolin thermoplastic polyurethane expanded graphite graphene rear earth heat stabilizers straight chain polyester plasticizers

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