摘要
采用示差扫描量热法(DSC)研究了聚丙烯/氨基化聚丙烯/纳米二氧化硅(PP/PP-g-NH2/SiO2)复合材料的非等温结晶行为。利用Caze法对结晶动力学进行了分析,Avrami指数n表明纳米SiO2和PP-g-NH2的加入改变了PP的结晶成核和生长机理;运用Dobreva法研究了纳米粒子的成核活性,结果表明纳米SiO2成核活性差,增容剂PP-g-NH2明显增强其成核活性;采用Friedman法分析了复合材料的结晶有效能垒,研究表明加入纳米SiO2使PP的结晶有效能垒降低,添加PP-g-NH2则进一步降低复合体系的结晶有效能垒;当纳米粒子含量为3%时,添加5%PP-g-NH2能有效提高纳米粒子成核活性,降低复合材料结晶有效能垒。
The nonisothermal crystallization behavior of PP/PP-g-NH2/nano-SiO2 composites was studied by differential scanning calorimetry （DSC）. The Caze method was applied to analyzing the nonisothermal crystallization kinetics. The Avrami exponents indicated that the mechanism of nucleation and growth of crystallization changed with the addition of SiO2 and PP-g-NH2. The Dobreva method was used to investigate the nucleation activity of silica nanoparticles on the polymer matrix. The results showed that silica had little nucleation activity, but the nucleation activity of silica was much improved with the addition of PP-g-NH2. The Friedman method was used to estimate the effective energy barrier for nonisothermal crystallization. The results revealed that nano-SiO2 decreased the effective energy barrier of PP, and the addition of PP-g-NH2 further decreased that of PP composites. When 3% nano-silica and 5% PP-g-NH2 were used, the nucleation activity of silica in composites was significantly improved and the effective energy barrier of PP was decreased.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2009年第4期1046-1051,共6页
CIESC Journal
关键词
聚丙烯
纳米二氧化硅
结晶动力学
成核活性
polypropylene
nano-silica
crystallization kinetics
nucleation activity
