Improvement in Processability for Injection Molding of Bisphenol-A Polycarbonate by Addition of Low-Density Polyethylene

Yuki Kuroda; Ken-Ichi Suzuki; Genzo Kikuchi; Nantina Moonprasith; Takumitsu Kida; Masayuki Yamaguchi

doi:10.3390/ma16020866

Improvement in Processability for Injection Molding of Bisphenol-A Polycarbonate by Addition of Low-Density Polyethylene

Materials (Basel). 2023 Jan 16;16(2):866. doi: 10.3390/ma16020866.

Authors

Yuki Kuroda¹, Ken-Ichi Suzuki¹, Genzo Kikuchi¹, Nantina Moonprasith^{2

3}, Takumitsu Kida², Masayuki Yamaguchi²

Affiliations

¹ Polymer Materials Research Laboratory, Tosoh Corporation, 1-8 Kasumi, Yokkaichi 510-8540, Mie, Japan.
² School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi 923-1292, Ishikawa, Japan.
³ Sirindhorn International Institute of Technology, Thammasat University, 99 Moo 18, Paholyothin, Khlong Luang 12120, Thailand.

Abstract

The rheological properties and processability at injection molding were studied for bisphenol-A polycarbonate (PC) that was modified by low-density polyethylene (LDPE) having a low shear viscosity. The LDPE addition significantly decreased the steady-state shear viscosity, especially in the high shear rate region. The decrease did not originate from slippage on the die wall but due to interfacial slippage between the PC and dispersed LDPE droplets that deformed to the flow direction to a great extent. As a result of the viscosity decrease, injection pressure largely decreased from 150 to 110 MPa with the addition only 5 wt.% of LDPE. The enhanced flowability also reduced the warpage of the molded product significantly, demonstrating that the processability at injection molding was improved by the addition of LDPE.

Keywords: injection molding; low-density polyethylene; polycarbonate; polymer blend; shear viscosity.

Grants and funding

This research received no external funding.