二乙二醇十八烷基醚单甲基丙烯酸酯及其聚合物的制备和表征

以二乙二醇十八烷基醚和甲基丙烯酰氯为原料, 采用醇钠-酰氯法合成了二乙二醇十八烷基醚单甲基丙烯酸酯(DEGOEMA), 并利用自由基聚合得到聚(二乙二醇十八烷基醚单甲基丙烯酸酯)(PDEGOEMA). 采用凝胶渗透色谱(GPC)分析测试了PDEGOEMA的分子量和分子量分布. 通过傅里叶变换红外光谱(FTIR)、 核磁共振氢谱(¹H NMR)、 差示扫描量热(DSC)、 热重(TG)和X射线衍射(XRD)对DEGOEMA和PDEGOEMA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, 这种新型单体及其聚合物是一种具有稳定的结构、 良好的结晶性能、 高相变焓及良好热稳定性的相变材料. PDEGOEMA的起始吸热温度为41 ℃, 起始放热温度为36 ℃, 热焓为73 J/g, 在314 ℃以下热稳定性良好, 可用于加工或使用温度较高的环境.

Preparation and Characterization of Diethylene Glycol Octadecyl Ether Methacrylate and Its Polymer

Diethylene glycol octadecyl ether methacrylate(DEGOEMA) as a phase change material was prepared by means of acrylation of diethylene glycol octadecyl ether sodium(C18E2Na) with methacryloyl chloride. And then poly(diethylene glycol octadecyl ether methacrylate)(PDEGOEMA) was synthesized by free radical polymerization. The molecular weight and its distribution were characterized using gel permeation chromatography(GPC). The structure, phase change properties, thermal stablility, crystal structure of the monomer and the comb-like polymer were characterized using Fourier transform infrared spectroscopy(FTIR), hydrogen nuclear magnetic resonance spectrum(¹H NMR), differential scanning calorimetry(DSC), thermogravimetric analysis(TG) and wide-angle X-ray diffraction(XRD). The results show that the novel monomer and polymers are excellent phase change materials with steady structure, high crystallinity, higher heat enthalpy and thermal stablility. Both the melting and crystallizing enthalpies of PDEGOEMA are 73 J/g. The onset melting temperature and crystallizing temperature are 41 and 36 ℃, respectively. It is thermal stable below 314 ℃. These properties indicate that this phase change material can be widely used as a polymeric phase change material in high processing and using temperature environments.