Nonisothermal Crystallization Kinetics of High-Density Polyethylene/Barium Sulfate Nanocomposites

作者：Chen Xiaolei; Wang Lumin; Liu Yongli; Shi Jiangao; Shi Hang

来源：Polymer Engineering and Science, 2009, 49(12): 2342-2349.

DOI：10.1002/pen.21483

The high-density polyethylene (HDPE)/barium sulfate (BaSO(4)) nanocomposites had been successfully prepared by melt-blending. Nonisothermal melt-crystallization kinetics of neat HDPE and HDPE/BaSO(4) nanocomposites was investigated with differential scanning calorimetry under different cooling rates. The nonisothermal crystallization behavior was analyzed by Ozawa, Avrami, and combined Ozawa-Avrami methods. It was found that the Ozawa method failed to describe the nonisothermal crystallization behavior of neat HDPE and HDPE/BaSO(4) nanocomposites. The modified Avrami method by Jeziorny was only valid for describing the middle stage of crystallization but was not able to describe the later stage of neat HDPE and HDPE/BaSO(4) nanocomposites crystallization. The value of Avrami exponent n for neat HDPE ranged from 3.3 to 5.7 and for HDPE/BaSO(4) nanocomposites ranged from 1.8 to 2.5. It is postulated that the values of n close to 3 are caused by spherulitic crystal growth with heterogeneous nucleation, whereas simultaneous occurrence of spherulitic and lamellar crystal growth with heterogeneous nucleation account for lower values of n. The combined Ozawa-Avrami method by Mo and coworkers (Polym. Eng. Sci., 37(3), 568 (1997)) was able to satisfactorily describe the crystallization behavior of neat HDPE and HDPE/BaSO(4) nanocomposites. In addition, the activation energy of nonisothermal crystallization was determined using the Kissinger (J. Res. Nath Bur Stand, 57(4), 217 (1956)) method, showing that the crystallization activation energy of HDPE/BaSO(4) nanocomposites was lower than that of neat HDPE. POLYM. ENG. SCI., 49:2342-2349, 2009.

• 出版日期2009-12
• 单位中国水产科学研究院东海水产研究所