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烯丙基醚改性不饱和聚酯树脂的空干性能研究 总被引:3,自引:0,他引:3
本文研究了氧气氛围中苯乙烯、烯丙基醚的氧化聚合机理和苯乙烯与烯丙基醚的氧化共聚机理,对烯丙基醚的空干性机理进行较为深入阐述,并应用差热扫描仪、扫描电镜、热谱仪和红外光谱仪等仪器和手段,探讨了不同饱和酸骨架和烯丙基醚含量对树脂性能的影响。 相似文献
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热塑性弹性体改性不饱和聚酯树脂的研究 总被引:5,自引:0,他引:5
本文采用共溶性SBS热塑性弹性体改性不饱和聚酯树脂,并对其力学性能和亚微观结构进行了测定。结果表明:不同系列的SBS对不饱和聚酯树脂韧性有提高,SEM测试表明该体系为共混多相体系。 相似文献
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烯丙基醚改性不饱和聚酯的合成 总被引:4,自引:0,他引:4
用对苯二甲酸二甲酯、丙二醇、马来酸酐以及三羟甲基丙烷二烯丙基醚合成了空干性不饱和聚酯 ,探讨了合成反应的条件 ,并与邻苯型、间苯型树脂作比较。 相似文献
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松香改性不饱和聚酯树脂的合成研究 总被引:11,自引:0,他引:11
松香与丙烯酸加成反应后代替邻苯二甲酸酐合成不饱和聚酯树脂具有放热温度低,收缩变型小的优点,有利于玻璃钢产品的加工成型设计。 相似文献
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叙述了在不饱和聚酯树脂(以下简称UP)的配方设计中,通过调节树脂的组分和添加剂以满足产品特定的要求,包括机械性能。 相似文献
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不饱和聚酯树脂改性研究进展 总被引:9,自引:2,他引:7
综述了不饱和聚酯树脂(UPR)改性的研究进展。介绍了收缩率控制机理,低收缩研究发展的4个阶段,低收缩剂LSA的典型代表——聚苯乙烯(PS),聚甲基丙烯酸甲酯(PMMA),聚醋酸乙烯(PVAc),PVAc-PS共聚物。讨论了UPR增韧改性方法,提高分子主链对称性,在分子结构中引入长链醇与长链酸,长链醇包括一缩二乙二醇、二缩三乙二醇及聚乙二醇;长链二元酸如己二酸等。此外还可加入热塑性弹性体,如液体橡胶、液体聚氨酯等以形成互穿网络结构增韧UPR。论述了提高UPR阻燃性的2种途径,即选用本质阻燃性树脂和向UPR中添加阻燃剂。介绍了含卤有机阻燃剂、无机阻燃剂、主链或主链与侧链均含磷的阻燃剂和赋予阻燃性的影响因素。介绍了部分采用可降解的植物纤维——竹纤维制备的UP复合材料和木粉改善UPR的性能。这些方法使不饱和聚酯树脂在低收缩性能、力学性能、阻燃性能等方面得到了改善,扩展了其应用范围。 相似文献
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不饱和聚酯树脂改性研究进展 总被引:5,自引:5,他引:5
综述了国内不饱和聚酯树脂(UPR)改性研究的最新进展,重点介绍了UPR增韧、增强、阻燃、耐热、耐环境介质改性以及降低其固化物收缩率的方法和机理。指出了UPR存在的问题和可能的发展方向。 相似文献
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对由不饱和聚酯和聚氨酯形成的不同组成的互穿网络聚合物的缺口冲击强度,拉伸强度及弯曲强度等力学性能进行了分析,并由透射电子显微镜观察了这种材料的形态结构,结果表明,当聚氨酯用量为10%~20%(质量分数)时,聚合物形成较好的互穿网络结构,使材料具有较高的冲击强度及拉伸强度,但对弯曲强度影响不大。 相似文献
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分别用甲苯二异氰酸酯(TDI)和六亚甲基二异氰酸酯(HDI)与蓖麻油(CO)反应制备出两种聚氨酯预聚体,再用预聚体与苯乙烯、丙烯腈、甲基丙烯酸甲酯、环氧树脂(E-44或E-51)等单体制备出蓖麻油聚氨酯互穿网络型聚合物(CO-PU IPN),研究了体系组成对该聚合物拉伸强度的影响。结果表明,随着固化时间的延长,CO-PU IPN的拉伸强度逐渐增大,TDI型CO-PU IPN比HDI型的拉伸强度大;烯类单体比环氧树脂单体所制CO-PU IPN的拉伸强度大,不同烯类单体之间的差别不大;增加预聚体中NCO/OH的摩尔比,CO-PU IPN的拉伸强度都是先增加,后减小,在摩尔比为2.25时出现最大值;添加抗氧剂1010、紫外光吸收剂UV-327和光稳定剂292等对CO-PUIPN的拉伸强度基本没有影响。 相似文献
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Interpenetrating polymer networks (IPNs) of polyurethane (PU)/polyacrylates have been synthesized by sequential polymerization of castor oil, methylene diisocyanate (MDI), and acrylate monomers such as methyl acrylate (MA), methyl methacrylate (MMA), and ethyl acrylate (EA); with benzoyl peroxide (BPO) and ethylene glycol dimethyl acrylate (EGDM) as an initiator and crosslinker, respectively. The physico‐mechanical properties, such as density, surface hardness, tensile strength, percentage elongation at break, and tear strength; and the optical properties, like total transmittance and haze, of PU/polyacrylate IPNs have been reported. Microcrystalline parameters of IPNs have been computed by using wide angle X‐ray scattering (WAXS) recordings. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 764–773, 2005 相似文献
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In this study, a carbon fiber/vinyl ester-polyurethane interpenetrating polymer network (IPN) laminate composite was fabricated and characterized for the first time. The IPN matrix, consisting of a commercially available vinyl ester and polyurethane, was synthesized via a sequential method with vinyl ester as the rigid phase and polyurethane as the flexible phase. Good compatibility between the two phases in the matrix was achieved and confirmed via differential scanning calorimetry and dynamic mechanical analysis. The thermomechanical response of the IPN matrix was compared with that of an unmodified vinyl ester resin. The presence of the more ductile polyurethane in the IPN matrix depressed the glass transition temperature (from 94 to 84°C), but also served to improve damping response at all frequencies studied. Tensile and flexural tests were performed on the carbon fiber/IPN and carbon fiber/vinyl ester composites to determine their mechanical response. The IPN composite exhibited lower tensile properties than the vinyl ester composite. However, its flexural properties were on par with those of the vinyl ester composite. 相似文献
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Polyurethanes obtained from 4,4′‐diphenylmethane diisocyanate (MDI) and polydiols with different molecular weights (polyethylene glycol and polyoxypropylene diols) were used as modifiers for diglycidyl ether of bisphenol A. Impact strength (IS), critical stress intensity factor (KC), flexural strength and flexural strain at break were measured as a function of polyurethane (PUR) type and content. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and infrared spectroscopy (FTIR) were employed for the structure and morphology analysis. It was found that the addition of polyurethane with an excess of isocyanate groups to epoxy resin resulted in the formation of a grafted interpenetrating polymer network structure. The mechanical properties of epoxy resin were improved with 5 and 10% PUR. Moreover, it was observed that composites containing PUR based on higher molecular weight (PUR 1002 and PUR 2002) with long flexible segments exhibited higher impact strength while PUR prepared from polyethylene glycol had a higher flexural energy to break and a higher flexural modulus. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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用傅立叶变换红外光谱(FTIR)研究纯聚氨酯弹性体和聚氨酯/聚二甲基硅氧烷IPN中聚氨酯的固化反应动力学。结果表明,在PU/PDMS IPN体系中聚氩酯的交联反应仍为二级反应,聚二甲基硅氧烷的存在大大降低了PU/PDMS IPN的交联速率,并提高了反应活化能。 相似文献
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Douglas J. Hourston Franz-Ulrich Schfer Nicholas J. Walter Michael H. S. Gradwell 《应用聚合物科学杂志》1998,67(12):1973-1985
The viscoelastic and mechanical properties and the morphology of polyurethane (PUR)/ olystyrene (PS) interpenetrating polymer networks (IPNs) containing ionic groups have been investigated. Dynamic mechanical thermal analysis (DMTA) revealed a pronounced change in the viscoelastic properties upon the introduction of ionic groups. For the 70 : 30 and 60 : 40 PUR/PS IPN compositions, the DMTA data changed from a dominant PUR to a dominant PS loss factor peak. Higher intertransition loss factor values indicated a significant improvement of IPN component mixing with increasing ionic content. The stress at break values increased only moderately, whereas sharp rises in Young's modulus and hardness values were found at 2 wt % ionic groups. At the same time, the strain at break values decreased by half. Scanning and transmission electron microscopy (TEM) indicated a grossly phase-separated morphology for the 70 : 30 PUR/PS IPN without ionic groups. With increasing methacrylic acid (MAA) content, the PS phase domain sizes decreased. At 2 wt % of ionic groups, a TEM micrograph showed interconnected PS phase domains resembling a network structure. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:1973–1985, 1998 相似文献
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测试了一系列以PU为第一网络的PU/EP/PBA三元IPN的力学性能,并详尽考究考察了其影响因素。通过研究,得到一类具有良好综合的弹性体,其拉伸强度和扯断伸长率可同时达到最佳值。研究表明,发迹合成条件,可达到控制调节材料性能的目的。第一网络的性质和组分间的相容性,是决定体系最终性能的两个重要方面。 相似文献
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Polyurethanes were obtained by the reaction of hydroxyl groups of castor oil with hexamethylene diisocyanate, isophorone diisocyanate or diphenylmethane diisocyanate using an NCO/OH ratio of 1.6. These polyurethanes were swollen in ethyl acrylate monomer and subsequently polymerized by radical polymerization initiated with benzoyl peroxide in the presence of the crosslinking agent ethylene glycol dimethacrylate. A series of interpenetrating polymer networks (PU/PEA IPNs) were obtained as tough films by casting in glass moulds. The characteristics of these films were determined: resistance to chemical reagents, thermal behaviour (DSC, TGA), tensile strength, Young's modulus, elongation at break (%) and Shore A hardness. The morphology was determined by scanning electron microscopy, and the dielectric properties such as electrical conductivity, dielectric constant (ε′), dielectric loss (ε″) and loss tangent (tan δ) were studied. 相似文献
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聚氨酯/聚苯乙烯互穿聚合物网络的结构与性能研究 总被引:3,自引:0,他引:3
通过改变组分比研究了PU/PS IPN结构与性能变化的规律。结果表明,在PU/PS为70/30时,电镜照片上呈现精细的细胞结构,相区尽寸缩小,网络间互穿程度最高,且溶胀度最低。热力学性能也同时出现最佳值, 相似文献