PHBV在玻璃化转变温度以上的物理老化行为

Physical Aging Behavior of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)(PHBV)above Tg

研究了聚(3-羟基丁酸酯-3-羟基戊酸酯)(简称PHBV)和含成核剂氮化硼(BN)的PHBV在30℃等温条件下老化过程中的热性能和弹性性能随老化时间的变化规律。根据聚合物三相模型理论,通过调制式差示扫描量热法(MDSC)计算得到PHBV的可动无定形相含量(X_(MA))、刚直无定形相含量(X_(RA))和结晶相含量(X_c)。结果表明,成核剂的加入对抑制PHBV的老化有明显效果。通过热性能、弹性性能和晶体形貌分析进一步证实了这一结果。

The changes of thermal and tensile properties of the pure poly （3-hydroxybutyrate-co -3- hydroxyvalerate） （PHBV） and PHBV containing boron nitride （BN） with aging time at 30 °C （above Tg） were studied. The mobile amorphous fraction （XMA ）,rigid amorphous fraction （ X RA ） and crystalline fraction （Xc） of PHBV were determined by modulated differential scanning calorimetry （MDSC） according to the polymer three-phase model. Results showed that addition of nucleating agent approach represented an efficient strategy to suppress the physical aging process of PHBV which was further confirmed by the dynamic mechanical and tensile properties data, as well as the crystal morphology.