Year 2020, Volume 12 , Issue 2, Pages 638 - 647 2020-06-30

Polypropylene/Chemical Blowing Agent Foams: Effect of the Injection Speed and Core Back Distance on Microstructure and Mechanical Properties

Meral AKKOYUN [1] , İbrahim BADEM [2] , Mert Emre ÖZTOKSOY [3] , Yeşim ASLAN [4]

In recent years, many parts of the automotive industry, previously made of metal, has been passed to polymers due to their light weight, ie lower carbon emission and fuel consumption advantage. The aim of this work was to investigate the microstructure and mechanical properties of chemical foaming agent added polypropylene foam samples produced by injection molding. In particular, the effects of injection speed and core back distance on the evolution of cell diameter, compact outer layer thickness, cell density and mechanical properties were examined. In the first step the effect of various injection speeds (110; 125; 140 mm/s) was investigated. Then, various core back positions (0; 0.7 and 1.5 mm) were analyzed at a constant injection speed (110 mm/s). The results showed an increase of the cell diameter, the compact outer layer thickness and the elastic modulus as the injection speed increases. In addition, an important effect of the core back distance was observed with the presence of a critical core back distance. Below this critical value, the cell diameter and the elastic modulus drop due to a notable decrease of the skin layer thickness. Above this critical value, the cells started to collapse and lose their circularity.
Polypropylene Foam, Chemical Blowing, Injection Molding, Core back, Microstructure, Mechanical Properties
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Primary Language en
Subjects Engineering
Journal Section Articles

Orcid: 0000-0002-8113-5534
Author: Meral AKKOYUN (Primary Author)
Country: Turkey

Orcid: 0000-0002-3595-7641
Author: İbrahim BADEM
Institution: Tofaş Türk Otomobil Fabrikası A.Ş.
Country: Turkey

Orcid: 0000-0002-4199-9768
Author: Mert Emre ÖZTOKSOY
Institution: Farplas Otomotiv A.Ş.
Country: Turkey

Orcid: 0000-0002-1649-1639
Author: Yeşim ASLAN
Institution: Karel Kalıp San. A.Ş.
Country: Turkey

Supporting Institution The Scientific Research Projects Units of Bursa Technical University
Project Number 172L09
Thanks Tofaş Türk Otomobil Fabrikası A.Ş., Farplas Otomotiv A.Ş. and Karel Kalıp San. A.Ş. are gratefully acknowledged for the production of PP/CBA foams at different processing conditions. The Scientific Research Projects Units of Bursa Technical University (under the contract number of 172L09) are also gratefully acknowledged for their financial support.

Publication Date : June 30, 2020

APA Akkoyun, M , Badem, İ , Öztoksoy, M , Aslan, Y . (2020). Polypropylene/Chemical Blowing Agent Foams: Effect of the Injection Speed and Core Back Distance on Microstructure and Mechanical Properties . International Journal of Engineering Research and Development , 12 (2) , 638-647 . DOI: 10.29137/umagd.711692