Structure-property relationships of polypropylene-based nanocomposites obtained by dispersing mesoporous silica into hydroxyl-functionalized polypropylene. Part 1: toughness, stiffness and transparency

Abstract

The long-range objective of this study is to provide better understanding of the relationship between the structures and properties of PP-based nanocomposites containing mesoporous silica (MPS). In this investigation, nanocomposites composed of MPSs with various porosity structures (two types of Santa Barbara Amorphous No. 15 (SBA-15) with pores of 4.4 or 8.0 nm, and Mobile Composition of Matter No. 41 (MCM-41) with pores of 2.9 nm) and polypropylene (PP) or functionalized PP containing hydroxyl groups (PPOH) were developed. Their physical properties were then evaluated. The nanocomposite containing PPOH and SBA-15 with a large pore size (SBA-15-L) showed higher toughness, stiffness, and transparency than the other nanocomposites. Our results indicated that the larger pore size of SBA-15-L and the high affinity between PPOH and the MPS surface led to an efficient pore-filled state of SBA-15-L with polymer molecules, forming a nanocomposite with better mechanical strength and transparency.