title: Effects of poly(L-lactide-ε-caprolactone) and magnesium hydroxide additives on physico-mechanical properties and degradation of poly(L-lactic acid).
abstract: BACKGROUND
  Biodegradable poly(L-lactic acid) (PLLA) is one of the most widely used polymer in biomedical devices, but it still has limitations such as inherent brittleness and acidic degradation products. In this work, PLLA blends with poly(L-lactide-ε-caprolactone) (PLCL) and Mg(OH)2 were prepared by the thermal processing to improve their physico-mechanical and thermal properties. In addition, the neutralizing effect of Mg(OH)2 was evaluated by degradation study.
  
  
  RESULTS
  The elongation of PLLA remarkably increased from 3 to 164.4 % and the glass transition temperature (Tg) of PLLA was slightly reduced from 61 to 52 °C by adding PLCL additive. Mg(OH)2 in polymeric matrix not only improved the molecular weight reduction and mechanical strength of PLLA, but also neutralized the acidic byproducts generated during polyester degradation.
  
  
  CONCLUSIONS
  Therefore, the results demonstrated that the presence of PLCL and Mg(OH)2 additives in PLLA matrix could prevent the thermal decomposition and control degradation behavior of polyester.
authors.affiliation: Center for Biomaterials, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792 South Korea ; Department of Biological Science, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841 South Korea.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Kang
authors.affiliation: Center for Biomaterials, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792 South Korea.
authors.forename: Eugene
authors.initials: E
authors.lastname: Lih
authors.affiliation: Department of Biological Science, Korea University, Anam-ro 145, Seongbuk-gu, Seoul 02841 South Korea.
authors.forename: Ik Hwan
authors.initials: IH
authors.lastname: Kim
authors.affiliation: Center for Biomaterials, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792 South Korea ; Department of Biomedical Engineering, Korea University of Science and Technology, Gajeong-ro 217, Yuseong-gu, Daejeon 34113 South Korea.
authors.forename: Yoon Ki
authors.initials: YK
authors.lastname: Joung
authors.affiliation: Center for Biomaterials, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 02792 South Korea ; Department of Biomedical Engineering, Korea University of Science and Technology, Gajeong-ro 217, Yuseong-gu, Daejeon 34113 South Korea.
authors.forename: Dong Keun
authors.initials: DK
authors.lastname: Han
keywords: Magnesium hydroxide; Neutralization; Poly(L-lactic acid); Poly(L-lactide-ε-caprolactone); Thermal decomposition