可化学回收的生物基环氧玻璃体

采用生物基缩水甘油醚季戊四醇双缩香草醛环氧树脂（DEPVD）为原料，经商用二苯二硫醚胺固化剂（AFD）固化得到生物基环氧玻璃体（DEPVD-AFD）。利用核磁共振氢谱（1H-NMR）对DEPVD的结构进行了表征。通过红外光谱（FTIR）、示差扫描量热仪（DSC）、热重分析仪（TGA）、拉伸测试机、降解回收实验等手段对环氧树脂的固化过程和综合性能进行了表征。结果表明，树脂材料具有较好的力学性能、热稳定性及降解性能，其玻璃化转变温度为143℃，拉伸强度为87.0 MPa，杨氏模量约为2 300 MPa,10%热失重温度为323℃。降解回收实验的结果表明，固化剂中含有的螺环缩醛结构赋予了环氧树脂可降解的特性。DEPVD-AFD能在H+浓度为0.1 mol/L的1,4-二氧六环溶液中完全降解（处理温度75℃，时间4 h），由于降解产物具有显著的溶解度差异，含有二苯二硫醚结构的高价值中间产物（DSS）可以通过水洗的方式进行简单高效的回收，DSS的FTIR和1H-NMR结果表明此中间产物具有明确的化学结构和较高的纯度，这种简单高效的回收方式有望为环氧玻璃体的化学回收铺平道路。     

可降解生物基含酯键环氧树脂的固化动力学研究

采用非等温差示扫描量热(DSC)法研究了可降解生物基含酯键环氧树脂固化动力学,分别建立了n级反应动力学模型、自催化模型以及结合n级反应和自催化模型的分段模型,并将模型预测值与实验数据进行了对比分析。结果表明,n级反应模型与实验曲线的偏差较大,自催化模型与实验曲线变化趋势基本一致,但仍然存在一定偏差,而结合两者的分段模型与实验曲线吻合较好,表明分段模型能更准确地描述该环氧树脂体系的固化反应过程,为其树脂基复合材料固化成型工艺条件优化提供理论指导。     

基于动态共价化学的可降解环氧树脂复合材料

先进环氧树脂基复合材料具有密度低、强度大、耐热和耐冲击等特点,已被广泛应用于航空航天、武器装备等领域。然而,具有三维网状交联结构的环氧树脂因不熔、不溶的特性而难以降解回收,造成环境污染和复合材料中昂贵的高性能纤维的损失。基于此,动态共价化学成为可降解热固性树脂设计与制备的优选方案之一。文章综述了基于Schiff碱键、六氢三嗪键、缩醛结构、D-A加成反应、二硫键等可降解环氧树脂的降解机理、制备方法、性能特征和应用发展,对可降解环氧树脂复合材料的国内外研究现状进行了梳理,并对该新兴热点领域的发展进行了展望。     

没食子酸聚乙二醇酯基环氧树脂的合成、固化及性能研究

以没食子酸丙酯和聚乙二醇200为原料,对甲苯磺酸为催化剂,在无溶剂条件下通过酯交换反应合成了没食子酸聚乙二醇酯GPE,并由其与环氧氯丙烷反应制备了环氧树脂GPEE。利用FT-IR对GPEE的结构进行了表征;以2-乙基-4-甲基咪唑为固化剂,利用DSC分析了GPEE的固化过程;利用DMA和TGA研究了固化物PGPEE的热机械性能和热稳定性,并与没食子酸基环氧树脂PGE进行了比较。研究结果表明:PGPEE的玻璃化转变温度为80.8℃,在氮气氛围下PGPEE失重5%和10%的温度分别为272和304℃;800℃时的残炭率为22%,具有良好的热机械性能和热稳定性。     

2536环氧树脂基复合材料的研制

对比了两种二氨基二苯砜的化学结构和区别；使用二氯原子取代的二氨基甲烷四缩水甘油胺（ＣＴＧＤＤＭ）环氧树脂和助剂作为基体。研制的２５２６环氧树脂基碳纤维复合材料具有很好的成型工艺性能，其综合力学强度满足设计指标要求。     

生物基环氧树脂研究进展

利用可再生原材料合成的无双酚A结构生物基环氧树脂属于环境友好材料,能有效解决双酚A固有的生理毒性问题,极具开发价值和社会经济效益。文中综述了近年来基于植物油、松香、木质素、生物酚、糖类等物质合成的生物基环氧树脂的最新研究进展。     

我国生物基及可降解塑料发展研究

在国家环保压力及国际国内双循环背景下,由于生物基及可降解塑料的优良特性,采用生物基塑料及可降解塑料制品是当前解决塑料污染问题的办法之一.目前我国生物基及可降解塑料存在回收体系不健全、与现有的循环再利用体系不兼容及生产成本较高的问题,需要从加强监管、正面引导及加快回收再利用技术的研发着手,加快我国生物基及可降解塑料的使用...     

阻燃型生物基环氧树脂的研究进展

利用植物油、衣康酸等可再生单体在环氧化作用下制备的环境友好型生物基环氧树脂可作为传统石油基环氧树脂的替代产品。增加生物基环氧单体或固化剂的功能、提高生物质含量和生物降解能力是未来开发高性能生物基环氧树脂的几个关键因素。本文综述了阻燃型生物基环氧树脂的现状和研究进展。     

有机硅对水性紫外光固化生物基环氧树脂的改性

以环氧树脂、衣康酸、柠檬酸、多种硅烷偶联剂为主要原料,经过开环、水解、脱水、接枝共聚等步骤,合成了多种有机硅改性水性紫外光固化生物基环氧树脂。探讨了反应温度对体系反应速率的影响,考察了中和剂种类、光引发剂种类及用量、硅烷偶联剂种类及用量对涂膜性能的影响。结果表明,当反应温度为100°C,中和剂为三乙胺,有机硅为乙烯基三乙氧基硅烷且其质量分数为环氧基的20%时,与未经改性的衣康酸-柠檬酸-环氧树脂相比,所制有机硅改性树脂及其涂膜性能良好:水接触角由41.497°增大到71.210°,铅笔硬度由H上升到6H,柔韧性由5 mm上升至2 mm,附着力1级,泡水24 h无明显变化。     

Chemical recycling of glass fiber reinforced epoxy resin cured with amine using nitric acid

An approach to chemical recycling of amine cured epoxy resin using nitric acid solution has been proposed [Dang W, Kubouchi M, Yamamoto S, Sembokuya H, Tsuda K. Polymer 2002;43:2953-8. [1]]. 1,8-p-Menthanediamine cured bisphenol F type (BPF/MDA) epoxy resin was decomposed in nitric acid solution, and then the decomposed product was repolymerized with original resin. In this paper, applicability of the proposed approach to glass fiber reinforced bisphenol F type epoxy resin cured with diamino diphenyl methane (DDM) was investigated. It was concluded that the approach was applicable to BPF/DDM epoxy resin, and potentially to all of amine cured epoxy resin. Flexural strength of the recycled resin was higher than that of virgin resin until the content of the neutralized extract, which was available from degradation of BPF/DDM epoxy resin, was not more than 30 wt% of the original resin. The reinforcement of glass fiber could be separated and recovered. The existence of the reinforcement did not affect decomposition the matrix.     

生物基环氧树脂的研究进展

以生物基原料合成环氧树脂是目前解决双酚A环氧树脂原料不可持续性和毒性问题最切实可行的方案。在综述国内外生物基环氧树脂研究进展的基础上,对最近几年我们基于松香、衣康酸、没食子酸合成生物基环氧树脂方面的研究进展进行了介绍,在此基础上进行了总结和展望。     

Synthesis of bio-based reactive N/P flame retardant and its curing and flame retarding behavior in epoxy resins

In this study, a pioneering bio-based nitrogen–phosphorus flame retardant and curing accelerator named oxime-phosphazene hexakis [(4-(hydroxyimino) 2-methoxy) phenoxy] cyclotriphosphazene (HAPV) was successfully synthesized using hexachlorocyclotriphosphazene and vanillin. When 5 wt % HAPV was added into epoxy, the limiting oxygen index increased from 22% to 27% and passed UL-94 V-0 (UL is defined as Underwriters Laboratories) rating. Meanwhile, with the addition 5 wt% HAPV, the apparent activation energy (E_a) of HAPV/EP decreased from 20.22 to 67.15 kJ/mol, and the pHRR value was suppressed from 581.21 to 330.18 kW/m². It was due to that the HAPV quenched the combustion chain reaction through the gas phase and condensed phase, forming a dense char layer for blocking the heat transfer. Overall, the study provides an environmentally friendly epoxy flame retardant curing accelerator that shows great potential in epoxy flame retardant applications.     

Dynamically cured polypropylene/epoxy blends

The dynamic vulcanization process, usually used for the preparation of thermoplastic elastomers, was used to prepare polypropylene (PP)/epoxy blends. The blends had crosslinked epoxy resin particles finely dispersed in the PP matrix, and they were called dynamically cured PP/epoxy blends. Maleic anhydride grafted polypropylene (MAH‐g‐PP) was used as a compatibilizer. The effects of the reactive compatibilization and dynamic cure were studied with rheometry, capillary rheometry, and scanning electron microscopy (SEM). The crystallization behavior and mechanical properties of PP/epoxy, PP/MAH‐g‐PP/epoxy, and dynamically cured PP/epoxy blends were also investigated. The increase in the torque at equilibrium for the PP/MAH‐g‐PP/epoxy blends indicated the reaction between maleic anhydride groups of MAH‐g‐PP and the epoxy resin. The torque at equilibrium of the dynamically cured PP/epoxy blends increased with increasing epoxy resin content. Capillary rheological measurements also showed that the addition of MAH‐g‐PP or an increasing epoxy resin content increased the viscosity of PP/epoxy blends. SEM micrographs indicated that the PP/epoxy blends compatibilized with PP/MAH‐g‐PP had finer domains and more obscure boundaries than the PP/epoxy blends. A shift of the crystallization peak to a higher temperature for all the PP/epoxy blends indicated that uncured and cured epoxy resin particles in the blends could act as effective nucleating agents. The spherulites of pure PP were larger than those of PP in the PP/epoxy, PP/MAH‐g‐PP/epoxy, and dynamically cured PP/epoxy blends, as measured by polarized optical microscopy. The dynamically cured PP/epoxy blends had better mechanical properties than the PP/epoxy and PP/MAH‐g‐PP/epoxy blends. With increasing epoxy resin content, the flexural modulus of all the blends increased significantly, and the impact strength and tensile strength increased slightly, whereas the elongation at break decreased dramatically. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1437–1448, 2004     

室温固化含磷膨胀型阻燃环氧树脂清漆

室温条件下以酸式磷酸酯固化环氧树脂,制得了含磷膨胀型阻燃清漆。涂膜的理化和燃烧性能测试表明,酸式磷酸酯具有较好的固化和阻燃效果。当酸式磷酸辛酯(m(双酯)/m(单酯)/m(磷酸)=44.38/54.73/0.89))与E-51按质量比6.5/8.7混合时效果最佳,表干时间230 min,烧穿时间76.5 min,残炭膨胀高度5.92mm。而市售G-03胺类固化剂固化的E-51,表干时间240 min,烧穿时间2.3 min,无残炭膨胀。FTIR检测结果显示,室温下酸式磷酸酯可使E-51固化;热分析以及SEM照片显示,酸式磷酸酯提高了炭层密度和残炭量。     

Use of inverse gas chromatography to quantify interactions in amine cured epoxy resins

Flory–Huggins interaction parameters, λ, were determined for a series of probes in an amine cured epoxy resin matrix (433–493 K) and its precursors (324–363 K) by inverse gas chromatography (IGC). Hildebrand–Scatchard theory was combined with Flory–Huggins theory in order to estimate infinte dilution solubility parameters (δ₂) for the matrix and its precursors at 298 K. It was shown that the value of the solubility parameter for the cured resin matrix lies between those of its precursors. Compared to the majority of published work, an unusual aspect of this application of IGC is that solubility parameters have been determined when the stationery phases are (i) small molecules and (ii) a highly crosslinked polymer. Moreover, all possible attempts have been made to ensure equilibrium conditions between probe and stationary phase, and compensation for asymmetry of peak profile has been applied in determining δ₂. The solubility parameters estimated by IGC are in good agreement with those calculated by other methods.     

环氧树脂改性超支化聚酯的合成及性能

以偏苯三酸酐、环氧氯丙烷及甲基丙烯酸缩水甘油酯为原料合成了超支化聚酯(HBP),再通过超支化聚合物的羧基与环氧树脂环氧基的反应得到环氧改性超支化聚合物;用GPC1、H-NMR、DSC、TGA表征了环氧改性超支化聚合物的结构和热性能;比较了不同环氧树脂用量改性前后树脂的光反应活性以及光固化涂层的耐擦洗性和硬度,测定了凝胶率-曝光时间曲线;以环氧改性超支化聚合物配制了光刻胶,在混合光源以及接触曝光的条件下,分辨率达到2~3μm,且图像十分清晰,断面整齐。环氧树脂用量为HBP羧基物质量的70%左右时,改性的超支化聚酯的光固化活性有明显提高,力学性能得到明显改进。     

纤维增强环氧树脂基复合材料的研究进展

综述了纤维增强环氧树脂基复合材料的应用及研究进展,其中包括玻璃纤维(GF)增强、碳纤维(CF)增强,芳纶纤维,混杂纤维及植物纤维增强等。     

无卤阻燃环氧树脂固化物及其结构与性能

环氧树脂固化物具有一系列性能优势,是重要的电子材料之一,但因其极易燃烧而存在火灾隐患。采用一类扭曲非对称结构的二氮杂萘酮型二胺和二酚型无卤阻燃固化剂,与双酚A型环氧树脂(E51)和含磷环氧树脂固化,所得固化物具有优异的热学和动态力学性能,T可达157℃,热线胀系数低;与含磷树脂固化后所得g材料的阻燃性顺利通过UL94 V-0级测试。     

有机硅/聚醚胺复合固化剂改性环氧树脂及其性能研究

以二甲基二乙氧基硅烷、γ-氨丙基三乙氧基硅烷、二苯基二甲氧基硅烷为单体,通过水解、缩聚制备了含有氨基活性功能基团的有机硅低聚物（PS）,然后以PS与聚醚胺与环氧树脂进行固化交联得到机硅改性环氧树脂,研究探讨了PS含量对改环氧树脂耐热性、力学性能及吸水性能的影响。结果表明：当PS添加量为基体树脂的30%时,改性树脂的耐热性能有明显提高,800oC残留量为26.45%,拉伸强度为68.27MPa,弯曲强度为81.68MPa,与水表面接触角为109.3°,吸水率为2.59%,比未改性树脂分别提高了17.24% ,6.6%,17.3%,21.3%和降低了0.12%。