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《Polymer》2014,55(26):6725-6734
Differential fast scanning calorimetry (DFSC) was employed on poly(butylene succinate) nanocomposites containing silver nanoparticles and multi-walled carbon nanotubes (MWCNT), in order to identify the temperature range of heterogeneous nucleation caused by both nanofillers. The fast scanning rates also allow investigating self-nucleation by recrystallization experiments approaching the crystallization temperature from low temperatures. The recrystallization behavior of PBSu and its nanocomposites is distinct from all other polymers studied so far as only the previously crystallized part of the material is able to recrystallize, independently on the available large number of nuclei. Since full melting of small crystals at low temperatures is observed this highlights the importance of ordered structures remaining in the polymer melt. On cooling from the melt the neat polymer did not crystallize at rates higher than 70 K/s, while the nanocomposites needed rates of 500 K/s and 300 K/s for silver and MWCNT, respectively. Below 280 K the crystallization kinetics of the matrix was almost the same with the nanocomposite samples. The nucleation mechanism changes at 280 K from heterogeneous to homogeneous. The study further confirms that below the glass transition nucleation and crystallization appears only after approaching the enthalpy value of the extrapolated supercooled liquid by enthalpy relaxation. 相似文献
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烯基琥珀酸淀粉在微胶囊壁材中的应用 总被引:4,自引:1,他引:3
介绍了烯基琥珀酸淀粉作为微胶囊壁材应用的原理,方法及其产品的性能,分析了它在我国实施产业化存在的问题,并提出今后的发展前景。 相似文献
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孙海龙 《现代塑料加工应用》2013,25(4):50-52
综述了脂肪族聚酯类可降解生物材料聚丁二酸丁二醇酯(PBS)的研究进展,重点对PBS的制备方法、改性、产业化等方面进行了探讨,指出PBS产业存在的问题及今后的研究重点。 相似文献
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Biodegradable polymeric composites were fabricated from poly(butylene succinate) (PBS) and kenaf fiber (KF) by melt mixing technique. The mechanical and dynamic mechanical properties, morphology and crystallization behavior were investigated for PBS/KF composites with different KF contents (0, 10, 20, and 30 wt %). The tensile modulus, storage modulus and the crystallization rate of PBS in the composites were all efficiently enhanced. With the incorporation of 30% KF, the tensile modulus and storage modulus (at 40°C) of the PBS/KF composite were increased by 53 and 154%, respectively, the crystallization temperature in cooling process at 10°C/min from the melt was increased from 76.3 to 87.7°C, and the half‐time of PBS/KF composite in isothermal crystallization at 96 and 100°C were reduced to 10.8% and 14.3% of that of the neat PBS, respectively. SEM analysis indicates that the adhesion between PBS and KF needs further improvement. These results signify that KF is efficient in improving the tensile modulus, storage modulus and the crystallization rate of PBS. Hence, this study provides a good option for preparing economical biodegradable composite. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
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PBS/剑麻复合材料制备与性能研究 总被引:1,自引:0,他引:1
利用蒸汽爆破预处理剑麻纤维(SESF)作为增强体,通过模压成型制备聚丁二酸丁二醇酯(PBS)/SESF复合材料,研究了SESF质量分数对复合材料力学性能的影响。对比了在剑麻纤维质量分数为30%的条件下,和未经预处理的2种剑麻纤维制得的复合材料的力学性能,并通过扫描电镜(SEM)对试样进行观察分析。结果表明,随着SESF质量分数的增加,复合材料的拉伸强度先增大后减小,在SESF质量分数为30%时达到最大值,比纯PBS的提高了15.5%;弯曲强度和弯曲模量均随剑麻纤维质量分数的增大而提高,其中弯曲强度在SESF质量分数为30%时的比纯PBS的提高了132.5%;断裂伸长率和冲击强度随着SESF质量分数的增加而降低。 相似文献
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