Next Article in Journal
Influence of Long-Term Storage on Shape Memory Performance and Mechanical Behavior of Pre-stretched Commercial Poly(methyl methacrylate) (PMMA)
Previous Article in Journal
A Stable Anti-Fouling Coating on PVDF Membrane Constructed of Polyphenol Tannic Acid, Polyethyleneimine and Metal Ion
Open AccessArticle

Toughened High-Flow Polypropylene with Polyolefin-based Elastomers

by Xiong Wang 1,*,†, Sheng Hu 2,†, Yi Guo 1, Guangquan Li 1 and Renwei Xu 1
1
Lanzhou Petrochemical Research Center, Petrochemical Research Institute, PetroChina, Lanzhou 730060, China
2
College of Chemical and Chemical Engineering, Xi′an Shiyou University, Xi’an 710065, China
*
Author to whom correspondence should be addressed.
Xiong Wang and Sheng Hu contribute equally to this article.
Polymers 2019, 11(12), 1976; https://doi.org/10.3390/polym11121976
Received: 14 October 2019 / Revised: 26 November 2019 / Accepted: 28 November 2019 / Published: 1 December 2019
(This article belongs to the Section Polymer Processing and Performance)
Polyolefin is the most widely used and versatile commodity polymer. In this work, three types of polyolefin-based elastomers (PBEs) were adopted to toughen a high-flow polypropylene to improve its overall performance. The chain microstructures of these PBEs, including ethylene/1-octene (E/O) random copolymer from Dow Chemical′s polyolefin elastomer (POE), olefin block copolymers (OBCs) of E/O from Dow, and ethylene/propylene random copolymer from ExxonMobil’s propylene-based elastomer, were elucidated by GPC, 13C NMR, TREF, and DSC techniques. The mechanical, thermal and optical properties, and morphology analysis of the PP/PBE blends were also studied to investigate the toughening mechanism of these PBEs. The results showed that all three types of PBEs can effectively improve the Izod impact strength of the PP/PBE blends by the addition of the rubber compositions, at the cost of the stiffness. PBE-1 and PBE-2 were found to have a great stiffness–toughness balance with about 1700 MPa of flexural modulus, about 110 °C of HDT and 3.6 kJ/m2 of impact strength on the prepared PP/PBE blends by forming separated rubber phase and refined spherulite crystals. As a result, the OBC with alternating hard and soft segments could achieve a similar toughening effect as the E/P random copolymer. Surprisingly, no obvious rubber phase separation was observed in the PP/PBE-4 blend, which might be due to the good compatibility of the E/P random chains with the isotactic PP; therefore, the PP/PBE blend obtains great toughness performance and optical transparency with the highest Izod impact strength of 4.2 kJ/m2 and excellent transparency.
Keywords: polypropylene; polyolefin-based elastomer; polyolefin elastomer (POE), olefin block copolymer (OBC), propylene-based elastomer; toughening effect polypropylene; polyolefin-based elastomer; polyolefin elastomer (POE), olefin block copolymer (OBC), propylene-based elastomer; toughening effect
Show Figures

Graphical abstract

MDPI and ACS Style

Wang, X.; Hu, S.; Guo, Y.; Li, G.; Xu, R. Toughened High-Flow Polypropylene with Polyolefin-based Elastomers. Polymers 2019, 11, 1976.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop