Malaysia Journal of Analytical Sciences Vol 18 No 3 (2014): 669 - 675

 

 

 

IMPROVEMENT OF MECHANICAL PROPERTIES OF POLY(LACTIC ACID) BY ELASTOMER

 

(Penambahbaikkan Sifat Mekanikal Poli (Asid Laktik) Oleh Elastomer)

 

Penwarat Sennan and Jantrawan Pumchusak*

 

Department of Industrial Chemistry, Faculty of Science

Chiang Mai University Chiang Mai 50200, Thailand

 

*Corresponding author: jantrawan@gmail.com

 

 

Abstract

Poly(lactic acid), PLA is a biodegradable thermoplastic that has a limited application due to its brittleness. This study has tried to overcome this weakness by blending polybutadiene (BR) into PLA. In the beginning period of the investigation, the preparation of PLA film with the thickness of less than 0.2 mm was prepared using the solvent casting method. The BR contents of 3, 5, 10 and 20 wt% were investigated. Vibracell sonicator was applied to disperse and lessen the rubber particle size in the PLA matrix. It was found that the elongation at break of the samples improved from 11 % for neat PLA to 39 % by blending with 10 wt%BR. However, tensile strength decreased as the BR contents was increased. SEM imaging revealed that the rubber has played an important role in the increase of sample toughness.

 

Keywords: polylactic acid, polybutadiene, biodegradable

 

Abstrak

Poli(asid laktik) (PLA) merupakan termoplastik biourai yang mempunyai aplikasi yang terhad kerana sifat kerapuhannya. Kajian ini cuba untuk mengatasi kelemahan tersebut dengan mengadunkan polibutadiena (BR) bersama PLA. Pada peringkat awal, penyediaan filem PLA dengan ketebalan kurang daripada 0.2 mm telah disediakan dengan menggunakan kaedah percampuran pelarut. Kandungan BR sebanyak 3, 5, 10 dan 20% berat telah dikaji. Sonikator Vibracell telah digunakan untuk menyebarkan dan seterusnya mengurangkansaiz zarah getah dalam matriks PLA. Kajian mendapati bahawa pemanjangan pada takat putus meningkat daripada 11% untuk matriks PLA kepada 39% untuk adunan yang ditambahkan 10% berat BR. Walau bagaimanapun, kekuatan tensil menurun dengan peningkatan kandungan BR dalam adunan. Pemeriksaan SEM membuktikan bahawa kehadirangetah telah memainkan peranan penting dalam peningkatan keliatan sampel.

 

Kata kunci: poli(asid laktik), polibutadiena, biourai 

 

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