【作者】 杨浩；

【导师】 陈庆华； 黄宝铨；

【作者基本信息】 福建师范大学 ， 高分子化学与物理， 2009， 硕士

【摘要】 超支化聚合物（HBP）由于其高度支化的结构而备受关注,因此研究HBP所具有的独特结构和性能特点之间的联系就显得十分重要。另一方面,大量末端基团以及低粘度的特性使得HBP在无机粒子表面接枝改性方面得以广泛应用。本论文通过动态流变学的方法观察超支化聚酰胺酯（HBPEA^S）相变过程中网络结构的变化以及HBPEA^S改性无机粒子对复合体系动态粘弹性的影响,并解释相应的作用机理,最终指导工业化生产。主要工作内容如下:（1）观察到HBPEA^S存在可逆的氢键网络结构且计算的活化能远大于理论值;成功地用Winter法描述了HBPEA^S化学凝胶网络的渐进式相变过程;由时温叠加原理计算出HBPEA^S的增强型松弛时间谱,并用修改后的Tuminello支化模型推导出HBPEA^S的分子量分布曲线（2）研究了炭黑（CB）填充丁苯（SBR）混炼胶在高、低CB含量下,HBPEA^S对CB粒子的改性效果。结果表明HBPEA^S的加入降低了CB粒子的表面能,显著改善了CB粒子在混炼胶中的分散效果:HBPEA^S与SBR分子链的相互作用以渗透缠结为主,HBPEA^S与CB粒子表面相互作用以范德华力为主:经过HBPEA^S改性的填充胶料,其硫化活化能显著降低且生成的硫化胶具有较低的滚动阻力。（3）研究了白炭黑（SiO₂）填充SBR混炼胶在高、低SiO₂含量下,HBPEA^S对SiO₂粒子的原位改性效果。结果表明在一定加工温度下,HBPEA^S的加入一方面其端羟基与SiO₂表面的硅醇基发生缩合反应,生成化学键;另一方面通过热运动扩散进入HBPEA^S空腔内的橡胶分子链,由于HBPEA^S的高温交联而被包封在空腔结构内。此外,HBPEA^S的加入能够减小胶料的硫化活化能,降低硫化温度。更多还原

【Abstract】 Hyperbranched plymers（HBP） represent a relatively new class of macromolecules that are characterized by a high degree of branching,numerous terminal groups,and low viscosities.As attempts have been made to exploit these unique properties for various uses,it has become clear that a better understanding of the relationship between hyperbranched structure and properties is needed.On the other hand,owing to the multi-terminal group and low viscosities,grafting HBP onto the filler surface which improve the fillers dispersion in polymeric compounds,is known to be one of the effective methods.The goal of this dissertation is to develop these understanding through the use of dynamic rheology:（1） We investigated the effects of temperature on the H-bonding structure of a hydroxyl functionalized hyperbranched polyesteramide（HBPEA^S） based on AB₂-type polymerization,the H-bonding activation energy was considerably bigger than the calculated theoretical values due to the multi-hydroxyl group structure.According to the dynamic viscoelasticity spectrum of HBPEA^S,the phase transition of HBPEA^S was also investigated,indicated the forming of chemical gel network.Furthermore,the relative molecular mass and distribution of HBPEA^S has been determined by the Enhanced relaxation time spectrum（ERTS）,compared to the univervsal GPC,the method is quite simple and repeartable.（2） The influence of addition of carbon black（CB） with HBPEA^S in CB filled SBR compounds was investigated.Rotary rheometer（AR-2000） was used to characterize the filler network and the interaction between CB and SBR by strain and temperature sweeps. The results showed that the use of HBPEA^S in the rubber compounds plasticized the surface between CB particles and SBR chains,attached to the CB surface so as to reduce the surface energy of the fillers.Furthermore,the dynamic rheological behaviors indicated that the interaction between CB and HBPEA^S was physical adsorption chiefly, and the interaction between SBR and HBPEA^S was the infiltration/tangles oriented mode. Finally,the rubber compounds modified with HBPEA^S showed lower activation energy of vulcanization and less rolling resistance.（3） The influence of in situ modification of silica（SiO₂） with HBPEA^S on filler network in SiO₂ filled SBR compounds was investigated.The results illustrated that the use of HBPEA^S in the rubber compounds not only reduce the surface energy of SiO₂ but also play a counpling effect between SiO₂ and SBR:on the one hand,the hydroxy terminated groups of HBPEA^S react with silanol groups by condensation,on the other hand,the rubber chains went into the big cavum of HBPEA^S through thermal motion, then enveloped in the cavum owing to the high-temperature crosslinking of HBPEA^S. Moreover,the use of HBPEA^S in rubber compounds also made lower activation energy of vulcanization and less rolling resistance.更多还原