刚韧平衡的高抗冲热塑性聚合物材料的设计和制备

刚性和韧性是决定聚合物材料能否用于工程材料的两个重要性能。聚丙烯作为广泛使用的通用高分子材料之一，由于抗冲击性能，尤其是低温抗冲击性能低限制了其在工程领域的应用。通过共混和釜内合金将橡胶或弹性体引入到聚丙烯基体内是制备高抗冲聚丙烯的有效方法和手段。但是，引入橡胶或弹性体增韧的同时，聚丙烯的刚性会大幅下降，这也不利于聚丙烯在工程领域的应用。因此，本项目拟将聚合物脆韧转变理论与多组分高分子体系的弹性理论相结合，建立脆韧转变临界点与材料弹性模量的关系，给出改性高抗冲热塑性聚合物的弹性模量所能达到的最高值，以及这一最高值与基体聚合物的性能和结构（结晶度、片晶厚度等）及增韧粒子的性能和结构（核壳结构）的关系，进而设计并通过物理共混的方法制备出具有高抗冲击性的刚韧平衡聚丙烯，为釜内合金技术大规模制备刚韧平衡聚丙烯提供科学依据。

Rigidity and toughness are two key parameters that determine whether a polymer can be used as an engineering material. Polypropylene (PP), used widely as a general polymeric material, its application is limited in engineering due to its poor impact resistance, especially at lower temperature. In general, the impact resistance for PP can be improved by alloying in reactor or by blending rubber or elastomer particles into the PP matrix. However, these methods can lead to a markedly decrease in rigidity, limiting the application of PP in engineering also. Therefore, by combining the brittle-ductile transition theory and the theory of elasticity in this project, we aim to establish the relation between the critical brittle-ductile transition point and the elasticity, give the maximal value that the rigidity can reach for high impact thermal plastic polymeric material and how this value depends on the structure (crystallinity, crystal thickness, et al) and properties of matrix polymer, the structure and properties of modifier (the size and modules of core and shell), and finally design and prepare the high impact PP with balanced toughness and rigidity by melting blending, and supply the scientific basis for the industrial manufacturing of the high impact PP with balanced toughness and rigidity by allying in reactor technique.