title: Thermal and mechanical characteristics of poly(L-lactic acid) nanocomposite scaffold.
abstract: Inorganic nanosized silicate nanoplatelets were incorporated into biodegradable poly(L-lactic acid) (PLLA) for the purpose of tailoring mechanical stiffness of PLLA porous scaffold systems. Increasing the nucleation density around the foreign body surfaces, the montmorillonite (MMT) nanoplatelets modified with dimethyl dihydrogenated tallow ammonium cations decreased the glass transition temperature and the degree of PLLA crystallinity, which seemingly caused the accelerated biodegradation rate of PLLA nanocomposites due to the enhanced segmental mobility of backbone chains and the expanded amorphous region of PLLA matrix. The tensile modulus was increased from 121.2MPa of pristine polymer scaffold to 170.1MPa of MMT/PLLA nanocomposite scaffold (ca. 40% increment) by the addition of small amount of MMT platelets (5.79 vol%) acting as a mechanical reinforcement of polymer chains in the nanoscale molecular level. Overall, the nanotechnology used in this study may be applied to various scaffold systems of biodegradable polymers and hard/soft scaffold structures requiring critical control and design characteristics of mechanical stiffness and biodegradation rate.
authors.affiliation: Department of Polymer Science and Engineering, University of Sung Kyun Kwan, Suwon 440-746, South Korea.
authors.forename: Jong Hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Tae Gwan
authors.initials: TG
authors.lastname: Park
authors.forename: Ho Sik
authors.initials: HS
authors.lastname: Park
authors.forename: Doo Sung
authors.initials: DS
authors.lastname: Lee
authors.forename: Young Kwan
authors.initials: YK
authors.lastname: Lee
authors.forename: Sung Chul
authors.initials: SC
authors.lastname: Yoon
authors.forename: Jae-Do
authors.initials: JD
authors.lastname: Nam
mesh_terms: D046508:Culture Techniques / Q000295:instrumentation* / Q000379:methods; D004548:Elasticity; D006358:Hot Temperature; D019344:Lactic Acid / Q000737:chemistry*; D008422:Materials Testing; D008567:Membranes, Artificial; D036103:Nanotechnology / Q000379:methods*; D044367:Phase Transition; D011091:Polyesters; D011108:Polymers / Q000737:chemistry*; D013499:Surface Properties; D013718:Tensile Strength; D023822:Tissue Engineering / Q000295:instrumentation* / Q000379:methods; D044366:Transition Temperature
chemical_list: D008567:Membranes, Artificial; D011091:Polyesters; D011108:Polymers; D019344:Lactic Acid; C033616:poly(lactide)