Thermal degradation of two different polymers bearing amide pendant groups prepared by ATRP method
作者:Kadir Demirelli、Esin Kaya、Mehmet Coşkun、Eyüp Bağci
DOI:10.1007/s10973-013-2986-6
日期:2013.11
Piperidinocarbonylmethyl methacrylate (PyCMMA) and 1-(piperidinocarbonyl) ethylmethacrylate (PyCEMA) monomers were synthesized. Polymerizations of PyCMMA and PyCEMA were carried out by atom transfer radical polymerization. The structure of monomers and polymers was characterized by 1H-NMR, 13C-NMR, and FT-IR spectroscopies. Characterization of poly(PyCMMA) and poly(PyCEMA) were carried out using differential scanning calorimetry and gel permeation chromatography. The experimental results showed that the reaction exhibited characteristics of controlled polymerization. The thermal degradation behaviors of poly(PyCEMA) and poly(PyCMMA) were studied using thermogravimetry and a single line vacuum system consisting of a degradation tube with a condenser for product collection. The poly(PyCEMA) and poly(PyCMMA) were heated from ambient temperature to 325 and 500 °C, respectively. The products of degradation were collected as a cold ring fraction (CRF). The CRFs of degradation were investigated by means of IR, 1HNMR, and GC-MS. For the degradation of both polymers, the major products of CRFs are piperidinocarbonyl methanol and 1,2-dipiperidino,1-oxo ethane. The GC-MS, IR, and NMR data showed that depolymerization below 325 °C to the corresponding monomer was not prominantin the thermal degradation of poly(PyCMMA). The mode of thermal degradation including formation of the major products was identified.
合成了哌啶羰基甲基甲基丙烯酸酯(PyCMMA)和 1-(哌啶羰基)乙基甲基丙烯酸酯(PyCEMA)单体。PyCMMA 和 PyCEMA 的聚合采用原子转移自由基聚合法进行。通过 1H-NMR、13C-NMR 和傅立叶变换红外光谱对单体和聚合物的结构进行了表征。使用差示扫描量热法和凝胶渗透色谱法对聚(PyCMMA)和聚(PyCEMA)进行了表征。实验结果表明,反应呈现出受控聚合的特征。使用热重计和单线真空系统研究了聚(PyCEMA)和聚(PyCMMA)的热降解行为,单线真空系统包括一个降解管和一个收集产物的冷凝器。聚(PyCEMA)和聚(PyCMMA)分别从环境温度加热至 325 和 500 ℃。降解产物以冷环馏分(CRF)的形式收集。通过红外光谱、1HNMR 和气相色谱-质谱对降解的 CRF 进行了研究。在这两种聚合物的降解过程中,冷环馏分的主要产物是哌啶甲醇和 1,2-二哌啶、1-氧代乙烷。气相色谱-质谱(GC-MS)、红外光谱(IR)和核磁共振(NMR)数据表明,在 325 ℃ 以下解聚成相应的单体并不是聚(PyCMMA)热降解的主要原因。确定了热降解的模式,包括主要产物的形成。