基于聚丙烯腈和聚乙二醇的侧链型相变材料的制备及表征

摘要

以不同分子量聚乙二醇(PEG)、4,4'-二苯基甲烷二异氰酸酯(MDI)、甲基丙烯酸羟乙酯(HEMA)、丙烯腈(AN)为主要原料,采用两步法先合成大分子单体(HMPEG),然后利用水相沉淀法,将大分子单体与丙烯腈(AN)以及第三单体甲基丙烯酸甲酯(MMA)接枝共聚,形成一种以丙烯腈和甲基丙酸甲酯聚合物P(AN-co-MMA)为主链,大单体(HMPEG)为侧链的系列接枝型相变材料P(AN-co-MMA)-g-HEPEG.通过傅里叶变换红外光谱(FT-IR)、差示扫描量热(DSC)、热重(TG)和X射线衍射(XRD)对大单体和共聚物的结构、相变行为、热稳定性和晶体结构进行了研究.结果表明,合成的大分子单体及其共聚物是一系列具有稳定的结构、良好的结晶性能、高相变焓及良好热稳定性的相变材料.当PEG分子量为4 000时(m(HMPEG)∶m(AN)=45∶45),接枝型相变材料P(AN-co-MMA)-g-HMPEG4000的熔融峰温度为52 ℃,结晶峰温度为26 ℃,热焓为31 J/g, 在290 ℃以下热稳定性良好,可用于加工或使用温度较高的环境.%Macromer (HMPEG) was prepared by a main raw material of different molecular weight polyethylene glycol (PEG), 4,4'twelve-diphenyl methane diisocyanate (MDI), hydroxyethyl methacrylate (HEMA), acrylonitrile (AN) in a two-step method firstly, and then graft copolymer was prepared by the macromonomer, acrylonitrile (AN) and a third monomer of methyl methacrylate (MMA) in water phase precipitation method.And a series of graft type phase change materials P (AN-co-MMA)-g-HEPEG that acrylonitrile and methyl propionate polymer as main chain and the macromonomer(HMPEG) as side chain were formed.The structure, phase transition behavior, thermal stability and the crystal structure of the macromonomer and the copolymer were studied by fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetry (TG) and X-ray diffraction (XRD).The results show that the synthesis of macromonomer and the copolymer are a series of phase change materials which have stable structure, good crystallization performance, high phase transition enthalpy and good thermal stability.When the PEG molecular weight is 4000 (HMPEG:AN=45:45), the melting peak temperature of graft type phase change material P (AN-co-MMA)-g-HMPEG4000 is 52 ℃, the cooling peak temperature is 26 ℃ and the enthalpy is 31 J/g.It has good thermal stability below 290 ℃, which can be processed or used in a high temperature environment.