Study of molecular weight and chain branching architectures of natural rubber. Issue 40 (29th June 2016)

• Record Type: Journal Article
• Authors: Qu, Wei; Zhu, Yong; Huang, Guangsu; Huang, Cheng; Luo, Ming‐Chao; Zheng, Jing
• Is Part Of: Journal of applied polymer science. Volume 133:Issue 40(2016)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2016-06-29
• Subjects: phospholipids -- properties and characterization -- proteins -- rubber; Polymers -- Periodicals; Polymerization -- Periodicals; 668.9
• DOI: 10.1002/app.43975
• Languages: English
• ISSNs: 0021-8995

Abstract

ABSTRACT: The origin of the unique bimodal molecular weight distribution (MWD) of natural rubber (NR) has been controversial up to now. Studying the connection between particle size and molecular weight (MW) might be a key approach to revealing the mystery of NR architectures. In this study, through constructing NR models as objectives and employing gel‐permeation chromatography coupled to a viscosity detector as well as a multiangle laser light scattering detector (GPC‐DP‐MALLS), we have acquired branching parameters for NR from solid experiments and data fitting. It is found that small rubber particles (SRPs) and large rubber particles (LRPs) jointly construct the unique bimodal MWD of NR. SRPs with low branching numbers (Bn) and branching frequency (λ) are believed to be composed of almost linear rubber molecules having no chain‐end groups to be branched. In contrast, LRPs transform their MWD curve into a clear bimodal peak after transesterification and possess high Bn. Meanwhile, the formation of branch points in LRP by hydrogen bonding and ionic linkages has been clearly confirmed. Thus, a clear and exact structure of NR has been revealed for the first time. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci, 2016. Abstract :