国内期刊荟萃

常温固化型酚醛环氧防腐涂料张善贵等.中国涂料,2004,(11):19常规的混拼型酚醛环氧防腐涂料,由于综合了环氧和酚醛树脂的特性,其涂层具有优良的机械性能和化学稳定性。但该涂料需要高温固化(150～200℃),从而限制了其实际应用。常温固化酚醛环氧树脂是由苯酚和甲醛制得的酚醛树脂与环氧氯丙烷反应生成的线型结构聚合物,该树脂分子中含有较多的环氧基(2.6～3.9个),可与脂肪胺或脂肪胺加成物在常温下反应固化形成结构紧密的涂膜。该涂膜不仅具有冷拼型酚醛环氧树脂涂料的性质,而且彻底解决了冷拼型酚醛环氧树脂涂料因需高温固化而在使用上受到…     

促进剂作用下环氧树脂与氰酸酯共固化反应的研究

本文研究了咪唑和乙酰丙酮过渡金属络合物对氰酸酯与环氧树脂体系共固化反应行为的影响,应用ＤＳＣ,ＦＴ－ＩＲ初步探索了在乙酰丙酮络合物促进作用下氰酸酯与环氧树脂体系的共固化反应机理,结果表明：加入促进剂可明显促进体系的共固化反应,降低反应温度,缩短反应时间,其反应机理：首先氰酸酯发生自聚反应形成二聚体及三嗪结构;然后二聚体可进一步反应形成三嗪,同时亦存在环氧树脂的聚醚反应最后是三嗪环开环与剩余的环氧树     

环氧改性酚醛树脂乳液性能研究

研究了环氧改性酚醛乳液粘接性能、固化反应、固化物热性能和微观形貌。实验结果表明:固化过程中发生了酚醛树脂与环氧树脂之间的化学反应。环氧改性酚醛乳液在固化中发生了从非均相变成均一相的观察,固化物的断裂面呈现一定的韧性断裂特征。在环氧加入量为20份时,环氧改性酚醛树脂乳液具有较佳的综合性能。     

季铵盐型水性环氧树脂乳化剂的制备及特性研究

以二乙醇胺、环氧E-44树脂等为原料,合成叔胺结构中间体,与溴乙烷反应制得季铵盐型水性环氧树脂乳化剂,以相反转技术乳化环氧树脂E-44.研究了乳化剂合成过程中反应温度、反应时间和环氧基转化率的关系;探讨了乳化剂用量对水性环氧树脂水分散性,稳定性及固化性能的影响.利用红外光谱对产物的结构进行了表征.结果表明:二乙醇胺与环氧E-44树脂在80 ℃反应3 h,环氧基转化率可达98%以上;乳化剂用量为ω=22%时其乳化效果及所制得乳液的稳定性最好.DSC和TG分析结果表明,水性环氧树脂乳液和工业环氧树脂E-44比较,固化后热性能基本一样,分解温度约在350 ℃,但其玻璃化转变温度有所降低,说明其韧性有一定提高.     

环氧树脂与氰酸酯共固化反应的研究—Ⅰ.固化反应行为、机理及其固化物结构特征

应用DSC、FT-IR对乙酰丙酮过渡金属络合物催化促进的环氧树脂与氰酸酯共固化反应行为、历程以及固化物的结构特征进行了研究探讨。结果表明,促进剂能够明显降低固化反应温度,缩短固化反应时间。反应历程首先是氰酸酯发生自聚反应形成二聚体或三聚体（三嗪环）,然后二聚体可进一步其聚形成三嗪环,此过程伴随着环氧基的聚醚反应,最后是三嗪环与剩余的环氧基反应形成恶唑烷酮,在氰酸酯适量的条件下,固化树脂中主要是恶唑烷酮和聚醚结构,三嗪环结构很少;在氰酸酯适量或过量条件下,固化树脂主要是三嗪环和恶唑烷酮结构,聚醚结构很少。     

液晶双4-环氧丙基乙氧基苯甲酸对苯二酚酯／DDE固化过程与形态

合成了双4-环氧丙基乙氧基苯甲酸对苯二酚酯液晶环氧树脂并对其进行了表征，研究了其与固化剂4，4-二氨基二苯醚（DDE）的固化行为和非等温固化反应动力学。用NMR、FTIR、DSC、动态力学谱、偏光显微镜等方法对其结构、固化行为和固化物的形态进行了表征。结果证明，该液晶环氧树脂为向列型液晶，熔点为119℃，清亮点为184℃。其与DDE固化反应的活化能为108．67kJ／mol，最佳固化温度为110～130℃，最高玻璃化温度为130℃。     

先进复合材料基体树脂的增韧研究

通过4种聚醚酰亚胺(PEI)PID、PIM、PIP和PIB改性3种热固性树脂(环氧、氰酸酯以及双马来酰亚胺树脂)的研究,讨论了PEI结构、用量、分子质量以及固化剂用量等因素对改性体系的相结构以及力学性能的影响,结果表明控制相结构是增韧基体树脂的关键因素,对基体树脂增韧的研究有指导意义。对不同的热固性树脂体系需采用不同的结构、配方和固化工艺。PIP改性环氧体系呈现的双连续相结构,PEI改性双马来酰亚胺体系,PEI质量分数为5%时呈现了PIM分散粒子相结构,PEI质量分数为10%时呈现了双连续相结构而PEI质量分数大于15%时呈现了相反转结构,PIP分子质量为18 000或20 000时呈现了双连续相结构,而对于PIP改性氰酸酯体系高PIP分子质量较低的呈现双连续相结构,该体系在120℃固化6 h呈现相反转结构,而150℃或180℃固化形成双连续相结构,双连续相结构增韧效果明显。     

热塑性PEI改性TGDDM环氧树脂的相分离研究

合成了四种不同化学结构的聚醚酰亚胺（PEI），以激光光散射（TRLS）和扫描电镜（SEM）等方法研究了PEI改性4，4‘－二氨基二苯甲烷四缩水甘油醚（TGDDM）环氧树脂／4，4‘-二氨基二苯砜（DDS）体系，讨论了PEI的化学结构，用量，分子量及固化剂用量对固化速率和相结构的影响，解释固化剂用量和PEI用量对粘结剪切强度的影响，同时考虑动力学和热力学因素对固化反应诱导相分离过程及相结构演变的作用，对相结构的控制提出了初步的设想。     

热固性环氧树脂改性沥青粘结剂的性能研究

以环氧树脂为沥青改性剂制备了热固性环氧沥青粘结剂。利用示差扫描量热仪(DSC)、动态热力学分析(DMA)、万能材料试验机和布氏旋转粘度计研究了环氧树脂改性沥青粘结剂的等温和非等温固化反应、玻璃化转变温度(Tg)、阻尼行为、力学性能和粘温特性。结果表明,环氧沥青粘结剂等温固化反应属于自催化反应,沥青的加入大大地降低了环氧树脂的固化热,其固化后只有1个Tg(远高于纯沥青的Tg),说明环氧树脂和沥青有很好的相容性。环氧沥青粘结剂还具有优异的阻尼行为,很高的拉伸强度和韧性。     

国外塑料专利

<正>专利名称:环氧树脂、环氧树脂组合物、环氧树脂固化产品和复合材料申请公布号:US2019338068(A1)申请公布日:2019.11.07本发明公开了一种环氧树脂,其包括具有介晶结构的第一环氧化合物和具有两个或两个以上与所述第一环氧化合物相同介晶结构的第二环氧化合物,比例由液相色谱法测定。所述第一环氧化合物相对于环氧树脂的总量,其含量在40%～50%。     

PEI及其改性物增韧环氧树脂研究

综述了Polyetherimide (PEI)及其改性物对环氧树脂的增韧研究进展。由于体系的相态结构是决定材料力学性能的重要因素 ,通过对PEI增韧TGDDM/DDS、Epikote82 8/DEAPA、TGAP/DAP、MY0 510 /DDS及HPT10 71/HPT10 61M等环氧树脂材料改性前后的相态结构和力学性能进行了分析比较 ,认为PEI对环氧树脂体系的增韧改性是成功的。     

Effect of tertiary polysiloxane on the phase separation and properties of epoxy/PEI blend

Epoxy functional siloxane (DMS-E09) was blended with epoxy resin (DGEBA) and thermoplastic polyetherimide (PEI). The results of morphology monitoring indicated that the reaction induced phase separation for all blends followed the spinodal phase separation mechanism. The microstructure changed from co-continuous of 25 wt% epoxy/PEI system to phase-inversion structure of 30 wt% epoxy/PEI system regardless of the content of the tertiary component DMS-E09. By comparing the onset time of phase separation between the two designated systems, the sequential occurrence of primary macrophase separation in co-continuous phase and secondary microphase separation in PEI-rich phase for 25 wt% epoxy/PEI system was identified. Studies of the thermomechanical properties of the DGEBA/PEI/DMS-E09 blends found that storage modulus increased with the addition of PEI but decreased with DMS-E09 monotonically. The value of T_g decreased with the addition of the tertiary DMS-E09 but was offset partially by the presence of PEI.     

Polymerization induced phase separation in poly(ether imide)-modified epoxy resin cured with imidazole

This paper studies the phase separation in poly(ether imide) (PEI) modified epoxy resin using imidazole (C₁₁Z-CNS) as epoxy hardener to control its morphology. The sponge-like phase structures were founded at higher PEI concentration (10-25 phr), while homogeneous structures are formed at low PEI concentration (5 phr). The effects of PEI concentration on curing kinetics and phase structures were studied by differential scanning calorimeters (DSC) and scanning electron microscopy (SEM). It is shown that although the addition of PEI does not change the curing mechanism, the separated morphology becomes finer at high PEI concentration. The curing rate and conversion decrease with the increase of the content of PEI. The chain growth polymerization of these systems caused an early gelation (conversion <10%) and early freezing of morphologies. The evolution of phase separation in the early stage was monitored by synchrotron radiation small angle X-ray scattering (SR-SAXS) and transmission electronic microscopy (TEM). It is suggested that the formation of sponge-like phase structure could be attributed to the strong viscoelastic effects in the early stage of phase separation.     

Characterization of cure reactions of anhydride/epoxy/polyetherimide blends

The cure kinetics of blends of epoxy (diglycidyl ether of bisphenol A)/anhydride (nadic methyl anhydride) resin with polyetherimide (PEI) were studied using differential scanning calorimetry under isothermal conditions to determine the reaction parameters such as activation energy and reaction constants. By increasing the amount of PEI in the blends, the final cure conversion was decreased. Lower values of final cure conversions in the epoxy/PEI blends indicate that PEI hinders the cure reaction between the epoxy and the curing agent. The value of the reaction order, m, for the initial autocatalytic reaction was not affected by blending PEI with epoxy resin, and the value was approximately 1.0. The value of n for the nth order component in the autocatalytic analysis was increased by increasing the amount of PEI in the blends, and the value increased from 1.6 to 4.0. A diffusion‐controlled reaction was observed as the cure conversion increased and the rate equation was successfully analyzed by incorporating the diffusion control term for the epoxy/anhydride/PEI blends. Complete miscibility was observed in the uncured blends of epoxy/PEI at elevated temperatures up to 120 °C, but phase separations occurred in the early stages of the curing process. © 2002 Society of Chemical Industry     

High-toughness,environment-friendly solid epoxy resins: Preparation,mechanical performance,curing behavior,and thermal properties

The development of a facile and efficient approach to prepare high-toughness epoxy resin is vital but has remained an enormous challenge. Herein, we have developed a high-performance environment-friendly solid epoxy resin modified with epoxidized hydroxyl-terminated polybutadiene (EHTPB) via one-step melt blending. The characterization, mechanical performance, curing behavior, and thermal properties of EHTPB-modified epoxy resin were investigated. EHTPB-modified epoxy resin exhibited excellent toughness with a 100% increase in elongation at break of tensile than that of neat epoxy resin. The transfer stress and dissipated energy in the rubber phase were predominant mechanisms of toughening. The toughening effect of EHTPB on solid epoxy resin was better than that of some of the previously reported liquid epoxy resins. Meanwhile, at 10 wt % of EHTPB loading, the EHTPB-modified epoxy resin displayed high strength and 22 and 101% improvement of flexural strength and impact strength, respectively. Moreover, at 10 wt % of EHTPB loading, the activation energy of EHTPB-modified epoxy resin for curing reaction decreased from 73.89 to 65.12 kJ·mol⁻¹, which is beneficial for the curing reaction. Furthermore, EHTPB-modified epoxy resin had a good thermal stability and the initial degradation temperature increased from 249 to 313 °C at 10 wt % of EHTPB loading. This work provides a simple-preparation and highly efficient and large-scale approach for the production of high-toughness environment-friendly solid epoxy resins. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48596.     

Poly(ether imide)‐modified benzoxazine blends: Influences of phase separation and hydrogen bonding interactions on the curing reaction

Polymer blends of polybenzoxazine (PBZ)/poly(ether imide) (PEI) were prepared by the in situ curing reaction of benzoxazine (BZ) resin in the presence of PEI. Phase separation induced by the polymerization of BZ resin was observed. The rheological behaviors, morphologies, and their evolution process of BZ/PEI blends were investigated by rheometer and scanning electron microscope. Phase separation that took place at the early stage of the curing reaction effectively reduced the dilution effect of PEI. Fourier transform infrared (FTIR) results suggested that hydrogen bonds between PBZ and PEI existed during the whole curing process, although weakened with phase separation. The decrease of isoconversion activation energy indicated that the polymerization of BZ resin was facilitated in the presence of such kind of hydrogen‐bonding interactions. By changing the weight fraction of PEI, extensive phase separation was obtained in PBZ blends with 5 and 20 wt % of PEI, in which systems, the crosslinking density and glass transition temperature (T_g) of PBZ‐rich phase were greatly improved compared to this single PBZ system. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

PHASE-SEPARATION BEHAVIOR IN POLY(ETHER IMIDE)-MODIFIED EPOXY BLENDS

Phase-separation behavior of aromatic amine-cured diglycidyl ether of bisphenol-A (DGEBA) epoxy oligomer and poly(ether imide) (PEI) engineering thermoplastic-modifier mixtures was investigated by means of small-angle light scattering (SALS) and optical microscopy. The starting reactant mixtures comprising epoxy, PEI, and the curing agents, namely diamino diphenyl sulfone (DDS) and methylene dianiline (MDA), were found to be single phase. During curing, phase separation occurred in the epoxy/PEI/DDS system, whereas no phase separation took place in MDA-cured epoxy/PEI blends. The difference between the two systems has been attributed to thermodynamic and kinetic aspects of cure reaction in thermoplastic-modified thermosetting (TMT) polymeric blends. Spinodal decomposition as characterized by an increase of scattered intensity, shift of the peak angle to a smaller scattering angle, and development of a regularly phase-separated structure followed by coarsening was found to be the dominant mechanism of reaction-induced phase separation in DDS-cured epoxy/PEI blend compositions.     

聚醚砜/环氧树脂共混体系流变特性与固化性能的研究

环氧树脂是一种性能优良的热固性树脂,但是存在抗冲击性能差的缺点。聚醚砜(PES)是一种高性能热塑性树脂,与环氧树脂共混能够改善环氧树脂的韧性。系统研究了不同PES含量的PES/环氧树脂共混体系的流变特性和固化性能。通过对等温粘度曲线的数据拟合分析,建立了粘度模型,分析了PES对PES/环氧树脂共混体系粘度的影响机理,并通过DSC测试研究了PES对共混体系固化性能的影响。结果表明,PES在环氧树脂中的溶解过程可以引起共混体系粘度的波动,PES的引入缩短了PES/环氧树脂共混体系的凝胶时间,而且PES中的羟基对环氧树脂的固化具有促进作用。