Synthesis of PLA-g-NR by Peroxide-Induced Melt-Grafting as a Biobased Impact Modifier for Poly (Lactic Acid)

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ธมลวรรณ จันทมุณี
แคทลียา ปัทมพรหม


A toughening agent from natural rubber grafted with poly (lactic acid) (PLA-g-NR) was prepared through melt grafting technique. The weight ratio of natural rubber (NR) to poly (lactic acid) (PLA) was 2 : 1, with di-tert-butyl peroxide (DTBP) as an initiator at 0–0.5 parts per hundred parts of rubber (phr). The structure of PLA-g-NR characterized by FTIR and 1H-NMR confirmed that PLA was successfully grafted onto NR. The rheological properties of PLA-g-NR were also different from those of the unreacted PLA-NR blend, indicating the presence of grafted structures. It was also found that this grafted PLA-g-NR possessed higher resistance to thermal degradation. The blending of the synthesized toughening agents with PLA at the content of 15 wt% revealed that the use of PLA-g-NR with 0.4 phr DTBP provided better dispersion of NR with a smaller rubber domain size than that in the unmodified PLA/NR blend. This indicated better phase compatibility between NR and PLA, which also resulted in an improvement in impact strength of the blend.


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ธมลวรรณ จันทมุณี

หน่วยวิจัยด้านรีโอโลยีและการขึ้นรูปของพอลิเมอร์ ภาควิชาวิศวกรรมเคมี คณะวิศวกรรมศาสตร์ มหาวิทยาลัยธรรมศาสตร์ ศูนย์รังสิต ตำบลคลองหนึ่ง อำเภอคลองหลวง จังหวัดปทุมธานี 12120

แคทลียา ปัทมพรหม, Department of Chemical Engineering, Faculty of Engineering, Thammasat University

หน่วยวิจัยด้านรีโอโลยีและการขึ้นรูปของพอลิเมอร์ ภาควิชาวิศวกรรมเคมี คณะวิศวกรรมศาสตร์ มหาวิทยาลัยธรรมศาสตร์ ศูนย์รังสิต ตำบลคลองหนึ่ง อำเภอคลองหลวง จังหวัดปทุมธานี 12120


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