The development of rigid amorphous fraction (RAF) in semi-crystalline syndiotactic polystyrene (sPS) with increasing crystallinity or crystalline fraction (CF) was investigated using standard differential scanning calorimetry (DSC). Bulk sPS samples with crystallinity levels as low as 11% were prepared via melt-quenching of compression-molded sPS; close-to-amorphous bulk sPS samples are difficult to obtain due to the intrinsic high crystallization rate of sPS. Cold-crystallization procedures were conducted on quenched sPS samples by isothermal annealing at different temperatures and timeframes. After cold-crystallization, the CF, RAF, and mobile amorphous fraction (MAF) of sPS samples were determined by DSC analysis based on heat capacity information. With increasing CF during cold-crystallization, RAF was maintained at ~16% in a CF range from 11 to ~25% and then gradually decreased to ~7% when the growth of CF ceased at ~50%. Specific RAF, i.e., the ratio of RAF to CF, exhibited a continuous reduction from 1.4 to 0.1 with increasing CF, indicating increasing crystal perfection and extent of decoupling of amorphous and crystalline regions with increasing cold-crystallization. Effects of sPS polymorphism (α vs. β forms of crystal cells) on RAF were also briefly considered. The α form, understood to be obtained to the exclusion of the β form by sPS cold-crystallization or at increasing levels with decreasing isothermal melt-crystallization temperature, leads to higher specific RAF than the β form at a given CF.

使用标准差示扫描量热法 (DSC) 研究了半结晶间规聚苯乙烯 (sPS) 中刚性无定形部分 (RAF) 随着结晶度或结晶部分 (CF) 的发展。结晶度低至 11% 的散装 sPS 样品是通过对压缩成型的 sPS 进行熔融淬火制备的；由于 sPS 固有的高结晶速率，很难获得接近无定形的块状 sPS 样品。通过在不同温度和时间范围内等温退火对淬火的 sPS 样品进行冷结晶程序。冷结晶后，sPS 样品的 CF、RAF 和移动无定形分数 (MAF) 通过基于热容信息的 DSC 分析确定。随着冷结晶过程中CF的增加，RAF 在 11% 至 ~25% 的 CF 范围内保持在 ~16%，然后当 CF 的增长停止在 ~50% 时逐渐下降到 ~7%。特定的 RAF，即 RAF 与 CF 的比率，随着 CF 的增加，显示出从 1.4 到 0.1 的连续降低，表明随着冷结晶的增加，晶体完美度和非晶和结晶区域的解耦程度增加。sPS 多态性的影响 (还简要考虑了 RAF 上的α与β晶胞形式。的α形式，应理解为获得到排除β由SP冷结晶形式或在随等温熔融结晶温度，导致了更高的比RAF比增加水平β在给定的形式CF.