Differential scanning calorimetry is used to obtain insights into the kinetics and thermodynamics of nanoconfined gelation. Gels of polyacrylonitrile in propylene carbonate, poly(vinyl alcohol) in ethylene glycol, and isotactic polypropylene in o-dichlorobenzene and decalin are studied in silica nanopores. Two major effects are observed for nanoconfined gels: a decrease in the heat of gelation and an increase in the gelation temperature. The smaller heat indicates that nanoconfinement of polymer chains results in the formation of fewer ordered crosslinks. The increased gelation temperature suggests acceleration of the gelation kinetics. The kinetics has been treated by an advanced isoconversional method and interpreted in terms of the Fisher–Turnbull model. It is found that acceleration of gelation in nanopores is associated with a decrease in the free energy barrier to nucleation, as one would expect for a change in the process mechanism from homogenous to heterogenous nucleation.

中文翻译：

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量热法检测聚丙烯腈，聚乙烯醇和等规聚丙烯的纳米约束凝胶

差示扫描量热法用于深入了解纳米约束凝胶化的动力学和热力学。碳酸亚丙酯中的聚丙烯腈凝胶，乙二醇中的聚乙烯醇和邻苯二甲酸等规聚丙烯凝胶在二氧化硅纳米孔中研究了二氯苯和十氢化萘。对于纳米封闭凝胶观察到两个主要作用：降低了胶凝热和提高了胶凝温度。较小的热量表明聚合物链的纳米约束导致形成较少的有序交联。升高的胶凝温度表明加速了胶凝动力学。动力学已经通过先进的等转换方法进行了处理，并根据Fisher-Turnbull模型进行了解释。已经发现，纳米孔中凝胶化的加速与成核的自由能垒的降低有关，因为人们期望过程机理从均相成核到异相成核。