环氧树脂/丙烯酸酯互穿网络聚合物及其流变性能研究

采用甲基六氢邻苯二甲酸酐( MeHHPA)作为新型脂环族环氧树脂(CER)的固化剂,选用过氧化二异丙苯为三羟甲基丙烷三甲基丙烯酸酯( TMPTMA)的引发剂,制备了一种新的CER/TMPTMA互穿网络聚合物( IPNs).通过扫描电子显微镜表征并证实了IPNs的形成过程.研究发现,由于TMPTMA的自由基聚合反应先于C...     

接枝改性环氧树脂/不饱和聚酯互穿聚合物网络的研究

研究了双酚A双烯丙基醚(ABE)对脂环族环氧树脂(CER)/三羟甲基丙烷三甲基丙烯酸酯(TMPTMA)分步互穿聚合物网络(SIPNs)的改性.利用扫描电子显微镜(SEM)考察了改性SIPNs形成的过程及最终固化物的微观结构,在此基础上研究了ABE用量对CER/TMPTMA SIPNs固化过程中的凝胶时间、最终固化物的力学性能及介电性能的影响.结果表明,ABE的加入没有改变CER/TMPTMA所形成SIPNs的结构,制得的改性SlPNs没有出现明显相分离现象.随着ABE用量的增加,改性SIPNs的冲击性能逐渐提高;当ABE用量为lO份时,改性SIPNs的弯曲性能最佳.ABE的加入还改善了改性SIPNs的介电性能,提高了改性SIPNs的电气强度.当ABE用量为20份时,改性SIPNs的电气强度最高.     

环氧树脂/三羟甲基丙烷三甲基丙烯酸酯互穿网络聚合物的微观结构和电性能研究

采用新型脂环族环氧树脂（CER）、甲基六氢邻苯二甲酸酐（MeHHPA）和三羟甲基丙烷三甲基丙烯酸酯（TMPTMA）作为基体树脂制备了一种崭新的互穿网络聚合物。由于TMPTMA的自由基聚合反应先于CER和MeHHPA的阳离子聚合反应,得到了一种分步互穿网络聚合物,最终分步互穿网络聚合物没有出现明显微观相分离现象。着重考察了TMPTMA含量对互穿网络聚合物电性能的影响。结果表明,CER/TMPTMA互穿网络聚合物在不同温度下的交流电阻与体系的组成和微观结构有关。随着TMPTMA含量的增加,CER/TMPTMA互穿网络聚合物的击穿强度和形态参数增大,互穿网络聚合物的均匀度逐渐增加,击穿机理趋于一致。     

多官能度UV固化松节油基聚氨酯丙烯酸酯的研究

以三羟甲基丙烷(TMP)、环氧丙醇及自制的松节油-马来酸酐(TMA)为原料,制备含有6个端羟基的聚酯,再以甲苯-2,4二异氰酸酯(TDI)、丙烯酸羟丙酯(HPA)进行封端,得到可UV固化的多官能度聚氨酯丙烯酸酯(PUA)。采用红外光谱(FT-IR)分别对制备出的聚酯及PUA进行了表征,并应用力学性能测试、热重分析考察了活性稀释剂种类及用量对固化涂膜物理性能和热性能的影响。结果表明:采用二丙二醇二丙烯酸酯(DPGDA)和三羟甲基丙烷三甲基丙烯酸酯(TMPTMA)复配活性稀释剂,m(DPGDA)∶m(TMPTMA)=4∶1,添加质量分数为20%时,固化膜综合性能较佳,固化膜初始分解温度约为245℃,另1分解温度约为390℃,耐热性能较好;利用凝胶法研究PUA的光固化行为表明其不饱和双键的最终转化率高达92%。     

环氧/聚氨酯共混灌浆材料的制备及性能

采用聚合物互穿网络技术与聚氧酯发泡技术相结合的方式制备了环氧/聚氨酯其混双组分灌浆材料.对浆材固化后的环氧/聚氨酯互穿网络结构(EP/PU IPNs)进行力学性能测试.结果表明,EP/PUIPNs固化物拉剪强度随时间的变化与环氧树脂固化物的一致,且优于聚氨酯和环氧树脂固化物的拉剪强度.固化2 min后和固化7 d后的IPNs红外光谱图对比分析表明,7 d后环氧基在914 cm-1处的特征峰明显削弱,2220 cm-1处异氰酸酯基特征峰消失,证明了环氧/聚氨酯互穿网络结构的形成.通过扫描电镜分析微观形态,当mEP/mPU =4/10时,浆材固结体2相相容性最佳.     

辐射增强PP/TAIC(TMPTMA)/PE共混体系相界面反应的研究——(Ⅰ)多官能团单体对形态结构及力学性能的影响

本研究中采用三烯丙基异腈脲酸酯(TAIC)和三羟甲基丙烷三甲基丙烯酸酯(TMPTMA)为PP/PE共混体系的多官能团单体。研究了辐照剂量,多官能团单体种类和多官能团单体用量对共混物形态结构及力学性能的影响。发现TAIC及TMPTMA对PP/PE体系有较好的增容作用,共混物具有好的相容性,力学性能得到改善。     

基于CDC技术电容层析成像系统的研究

针对电容层析系统中的微小电容的检测问题,设计了一套以AD7746为核心芯片的微小电容在线检测装置,该装置是以八电极圆形管道为模型,通过电容数字转换技术(CDC)对微小电容进行检测。与传统的AC电桥测量装置相比,电容检测电路得到简化;与充/放电原理电容检测相比,不存在电荷注入和零点漂移,提高了电容检测系统的稳定性和精确性。同时利用有限元计算了灵敏度,使用线性反投影法(LBP)进行成像,该装置对实际的两相流在线检测具有非常重要的现实意义。     

辐射引发界面反应改善PP/LDPE体系力学性能

利用辐射引发的界面反应来改善聚丙烯/低密度聚乙烯(PP/LDPE)共混体系的力学性能.研究了多官能团单体三聚异氰酸三烯丙酯(TAIC)、三羟甲基丙烷三甲基丙烯酸酯(TMPTMA)对PP/LDPE共混体系的相态结构、力学性能的影响.结果表明,引入多官能团单体后,PP,LDPE两相界面模糊,经过35 kGy的辐照,含有多官能团单体的共混体系的拉伸强度、拉伸断裂能、断裂伸长率均得到了大幅度提高.     

DCPDE/PUR互穿聚合物网络的制备与表征

以聚氨酯(PUR)预聚体、二氧化双环戊二烯环氧树脂(DCPDE)为基体,分别以顺丁烯二酸酐(MA)和甘油为固化剂和促进剂,制备了新型DCPDE/PUR互穿聚合物网络(IPNs)复合材料。采用红外光谱法、热重分析法和差示扫描量热法等手段对该IPNs材料的化学结构、热性能和力学性能进行了表征。结果表明,PUR加入DCPDE固化体系,形成了IPNs结构,提高了复合材料的韧性,降低了刚性。PUR质量分数为30%时,复合材料的拉伸强度相对稳定,冲击强度提高了16.4 kJ/m2,断裂伸长率提高了12.4%,弯曲强度略微降低;复合材料的热分解温度在360℃以上,热稳定性良好。     

环氧树脂/DMP30体系的微波固化及性能研究

针对目前环氧树脂/固化剂体系微波固化的研究现状,通过预凝胶处理和间歇固化相结合的方法,初步研究了环氧树脂/DMP30[2,4,6-三(二甲胺基甲基)酚]体系的微波固化条件,利用红外光谱研究了微波固化过程,并表征了产物的结构和力学性能。实验结果表明,与传统热固化相比,微波固化可以明显缩短固化时间、降低能耗;微波固化产物和热固化产物具有相同的产物结构;微波固化产物具有更高的弯曲模量和弯曲强度,热固化产物的冲击强度略高一些。     

On-line monitoring of cycloaliphatic epoxy/acrylate interpenetrating polymer networks formation and characterization of their mechanical properties

The novel interpenetrating polymer networks (IPNs) based on cycloaliphatic epoxy resin (CER) containing cyclohexene oxide groups and tri-functional acrylate, trimethylol-1, 1, 1-propane trimethacrylate (TMPTMA) were synthesized. The formation of the IPNs was on-line monitored by means of polarizing optical microscope, time-resolved light scattering and Fourier transform infrared spectroscopy. The morphological and mechanical properties of the resultant IPNs were investigated and evaluated with scanning electron microscopy (SEM) and dynamical thermal mechanical analysis (DTMA), respectively. The on-line monitoring results showed that during the course of the IPNs formation, the TMPTMA component was cured more quickly than the CER component, leading to the formation of the sequential IPNs. During the early curing stage, there were the phase separation phenomena in the CER/TMPTMA system. The SEM results revealed that although there were some slight phase separation phenomena in the CER/TMPTMA system in the early curing stage, the resultant IPNs displayed the homogeneous structures and did not show the apparent phase separation morphology. The DTMA results revealed that the resulting IPNs exhibited rather higher modulus and denser cross-linking network structure than the neat CER system.     

Morphology and thermal and dielectric behavior of cycloaliphatic epoxy/trimethacrylate interpenetrating polymer networks for vacuum‐pressure‐impregnation electrical insulation

Vacuum pressure impregnation has been known as the most advanced impregnation technology that has ever been developed for large and medium high‐voltage electric machines and apparatuses. We developed one new type of vacuum‐pressure‐impregnation resin with excellent properties by means of a novel approach based on in situ sequential interpenetrating polymer networks resulting from the curing of trimethacrylate monomer [trimethylol‐1,1,1‐propane trimethacrylate (TMPTMA)] and cycloaliphatic epoxy resin (CER). In this study, the influence of the concentrations of the components and their microstructures on their thermal and dielectric behaviors were investigated for the cured CER/TMPTMA systems via atomic force microscopy, dynamic mechanical analysis, thermogravimetric analysis, and dielectric analysis. The investigation results show that the addition of TMPTMA to the CER–anhydride system resulted in the formation of a uniform and compact microstructure in the cured epoxy system. This led the cured CER/TMPTMA systems to show much higher moduli in comparison with the pure CER–anhydride system. The thermogravimetric analysis results show that there existed a decreasing tendency in the maximum thermal decomposition rates of the cured CER/TMPTMA systems, which implies that the thermal stability properties improved to some extent. The dielectric analysis results show that the cured CER/TMPTMA systems displayed quite different dielectric behaviors in the wide frequency range 0.01 Hz–1 MHz and in the wide temperature range 27–250°C compared with the cured CER–anhydride system. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

The influence of different components on interpenetrating polymer network's (IPN's) characteristics as automotive top coats

The aim of this study was to investigate the influence of different components of interpenetrating polymer networks (IPNs) on their behavior in dual curing automotive applications. Dual curing is one of possible ways to obtain fast curing, scratch resistant coatings for use in OEM and car refinish applications. Dual curing systems, upon hardening, represent interpenetrating networks (IPNs) [1]. IPN's were obtained using novel acrylate-terminated hyperbranched polyester with high functionality and compared to classical 2-pack polyurethane clear coat.     

聚氨酯/环氧树脂互穿网络聚合物反应动力学

通过共混法制备了聚氨酯(PU)/环氧树脂(EP)互穿网络聚合物(IPN),采用示差扫描量热法(DSC)和动态机械分析(DMA)对IPN形成过程中的固化反应动力学及产物IPN的相容性进行了研究,结果表明,m(PU)/m(EP)=10∶6的IPN体系的反应级数为0.95,表观活化能为169.23 kJ/mol;PU/EP IPN只有1个玻璃化转变温度,相容性好。     

Curing and mechanical properties of dicyanate/poly(ether sulfone) semi‐interpenetrating polymer networks

Semi‐interpenetrating polymer networks (semi‐IPNs) composed of a dicyanate resin and a poly(ether sulfone) (PES) were prepared, and their curing behavior and mechanical properties were investigated. The curing behavior of the dicyanate/PES semi‐IPN systems catalyzed by an organic metal salt was analyzed. Differential scanning calorimetry was used to study the curing behavior of the semi‐IPN systems. The curing rate of the semi‐IPN systems decreased as the PES content increased. An autocatalytic reaction mechanism was used to analyze the curing reaction of the semi‐IPN systems. The glass‐transition temperature of the semi‐IPNs decreased with increasing PES content. The thermal decomposition behavior of the semi‐IPNs was investigated. The morphology of the semi‐IPNs was investigated with scanning electron microscopy. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1079–1084, 2003     

Controlling properties of acrylate/epoxy interpenetrating polymer networks by premature termination of radical polymerization of acrylate

An approach is presented to control properties of sequentially synthesized acrylate/epoxy interpenetrating polymer networks (IPNs) and is used to print uniform and graded properties. These IPNs are constructed by partial formation of the acrylate network, removal of the excess components, expansion with the epoxy system, and curing. The partial crosslinking of the initial network is controlled by photo polymerization and used to manipulate the final properties. The process is used to print homogeneous and graded IPNs with properties in the range of 10 to 1000 MPa. The curing of acrylate, the control mechanism, is studied by Fourier Transform Infrared Spectroscopy (FTIR) during curing on a temperature and environment controlled attenuated total reflection system. Fast scanning calorimetry is used to study network formation, nanoindentation is used to characterize local change of modulus, and uniaxial tensile testing is used to characterize stress response of the printed systems. POLYM. ENG. SCI., 59:1729–1738 2019. © 2019 Society of Plastics Engineers     

聚氨酯／乙烯基酯树脂互穿聚合物网络合成动力学及相容性

以丙烯酸乙酯为乙烯基酯树脂的共聚单体,利用“同步互穿”工艺室温固化制备了一系列聚氨酯／乙烯基酯树脂互穿聚合物网络 (PU/VER IPN).对IPN固化过程的动态跟踪及半定量考察的结果表明：由于两网络不同的聚合机理及体系黏度的影响,PU网络先形成,网络形成得较完善.采用示差扫描量热仪 (DSC)、原子力显微镜 (AFM)及透射电镜 (TEM)定性考察了IPN两网络间的相容性,结果表明：形成的双相连续“同步互穿”体系的相畴尺寸在纳米级范围,当PU 和VER的组成比为80/20和70/30时体系均出现一个玻璃化转变温度 (T_g),较好地改善了PU与常规VER树脂的相容性.进一步通过DSC实测和理论T_g值的计算获得相容因子 (θ),定量考察了两网络间的相容性.     

互穿网络聚合物研究及其应用进展

综述了互穿网络聚合物(IPNs)的分类、结构和制备材料,着重讨论了IPNs在各方面的应用,指出了目前IPNs材料制备存在的问题,并对今后IPNs的制备和研究进行了展望,提出了制备IPNs新思路.     

Morphologies and applied properties of free radical/cationic UV‐cured CPUA/TMPTMA/CER composite films

A UV‐cured composite film was prepared by free free‐radical photopolymerization from a blend containing oligomer cycloaliphatic polyurethane acrylate (CPUA) and reactive diluent trimethylolpropane trimethaacrylate (TMPTMA) with the same weight (coded as UT) in the presence of free free‐radical photoinitiator Irgacure 754. It was proved to be a homogeneous system featuring only one phase by means of scanning electron microscopy (SEM). Cycloaliphatic epoxy resin (CER) was introduced to enhance mechanical properties of the UV‐cured UT composite film in the presence of cationic photoinitiator Irgacure 250, and a series of UV‐cured CPUA/TMPTMA/CER composite films with different component ratios were prepared by free radical/cationic hybrid UV UV‐curing technique. Results of conversion curves, SEM, and Fourier‐ transform infrared spectroscopy illustrated that UT was cured faster than CER, leading to dynamically asymmetric photopolymerization‐induced phase ‐separation behaviors. The thermal and mechanical properties were evaluated via thermal degradation analysis, dynamic mechanical analysis, and stress–strain curves. Surface properties such as pencil hardness, pendulum hardness, shrinkage rate, contact angle, flexibility, and glossiness were also studied. All these measurements revealed that component ratios, intermolecular attractions, photopolymerization velocities, and viscosities had remarkably influenced on the morphologies and applied properties of UV‐cured composite films, and interpenetrating polymer network films had better comprehensive performances than other UV‐cured composite films with different microstructures. POLYM. COMPOS., 36:1177–1185, 2015. © 2014 Society of Plastics Engineers