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首页> 外文期刊>Journal of Applied Polymer Science >Synthesis, characterization, and thermal degradation studies of copolymer resin derived from p-cresol, melamine, and formaldehyde
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Synthesis, characterization, and thermal degradation studies of copolymer resin derived from p-cresol, melamine, and formaldehyde

机译：对甲酚，三聚氰胺和甲醛衍生的共聚树脂的合成，表征和热降解研究

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Copolymers (p-CMF) synthesized by the condensation of p-cresol and melamine with formaldehyde in the presence of an acid catalyst and using varied molar proportion of the reacting monomers. Copolymer resin compositions were determined on the basis of their elemental analysis. The number average molecular weight of these copolymers was determined by conductometric titration in nonaqueous media. Solution viscosity measurements in dimethyl sulfoxide (DMSO) were carried out to ascertain the characteristic functions and constants of the copolymer resins. The copolymer resins were further characterized by UV-visible absorption spectra in the nonaqueous medium, Infra-red (IR) spectra, and the nuclear magnetic resonance (NMR) spectra. Thermal studies of the resins were carried out to determine their mode of decomposition, the activation energy (E-a), order of reaction (n), frequency factor (Z), entropy change (Delta S), free energy change (Delta F), and apparent entropy change (S*). Thermal decomposition curves were discussed with careful attention of minute details. The Freeman-Carroll and Sharp-Wentworth methods have been used to calculate thermal activation energy and thermal stability. Thermal activation energy (E-a) calculated with these methods are in agreement with each other. The data from the Freeman-Carroll methods have been used to determine various thermodynamic parameters. The order of thermal stability of copolymers has been determined using TGA. (C) 2008 Wiley Periodicals, Inc.
机译：通过在酸催化剂的存在下，对甲酚和三聚氰胺与甲醛缩合合成的共聚物（p-CMF），使用不同摩尔比例的反应单体。共聚物树脂组合物根据其元素分析确定。这些共聚物的数均分子量通过在非水介质中的电导滴定法确定。进行了在二甲基亚砜（DMSO）中的溶液粘度测量，以确定共聚物树脂的特征功能和常数。通过在非水介质中的UV-可见吸收光谱，红外（IR）光谱和核磁共振（NMR）光谱进一步表征共聚物树脂。进行了树脂的热研究，以确定它们的分解方式，活化能（Ea），反应顺序（n），频率因子（Z），熵变（Delta S），自由能变化（Delta F），和表观熵变化（S *）。仔细关注细节，讨论了热分解曲线。 Freeman-Carroll和Sharp-Wentworth方法已用于计算热活化能和热稳定性。用这些方法计算出的热活化能（E-a）彼此一致。 Freeman-Carroll方法的数据已用于确定各种热力学参数。共聚物的热稳定性的阶数已使用TGA确定。 （C）2008 Wiley期刊公司

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