Thoughening of poly(lactic acid) with silicone rubber

Abstract

In this study, poly(lactic acid) (PLA) was blended with silicone rubber (SR) to improve its impact strength and toughness by using dynamic crosslinking in the presence of peroxide during melt compounding. The SR to PLA ratio, peroxide and coagent concentrations were taken as experimental parameters. Blends were evaluated in terms of their thermal properties, tensile and impact strengths, dynamic mechanical properties, and micro‐structure. Results showed that PLA was successfully toughened with SR using dynamic crosslinking. Impact strength and energy of fracture in tensile test improved up to 4 and 10 times, respectively. On the other hand, yield strength and stiffness of blends deteriorated by the incorporation of SR. Thermal analysis pointed out that presence of SR decreased the cold crystallization temperature. It was observed from scanning electron microscopy (SEM) that the energy absorbing mechanism under impact loads in PLA/SR blends is tortuosity in the crack patterns. POLYM. ENG. SCI., 54:2029–2036, 2014. © 2013 Society of Plastics Engineers

A review on degradation mechanisms of polylactic acid: Hydrolytic, photodegradative, microbial, and enzymatic degradation

“…[99,100] PLA has been employed in biomedical applications such as bone screws, sutures and tissue engineering scaffolds. [32,71,[101][102][103][104] Synthetic biodegradable materials such as PLA, poly-glycolic acid (PGA), and poly-caprolactone (PCL), along with their copolymers, are used in biomedical devices since they are biocompatible. In general, PLLA is widely used in the biomedical field due to its biodegradability, biocompatibility, thermal plasticity and its suitable mechanical properties.…”

Combined effect of a plasticizer and carvacrol and thymol on the mechanical, thermal, morphological properties of poly(lactic acid)

“…It is a linear aliphatic thermoplastic polyester that is generally produced from lactic acid by ring‐opening polymerization . Despite its promising features, including its optical clarity, high strength and modulus, and easy processing in conventional equipment, the widespread use of PLA is limited because of its brittleness and low crystallization rate …”

“…4 Despite its promising features, including its optical clarity, high strength and modulus, and easy processing in conventional equipment, the widespread use of PLA is limited because of its brittleness and low crystallization rate. 5 Previous studies have reported the use of plasticizers for the improvement of PLA properties. [6][7][8][9] Plasticizers are widely used in the plastics industry to improve the processability, flexibility, and ductility of glassy polymers.…”

PLA/SEBS Bioblends: Influence of SEBS Content and of Thermal Treatment on the Impact Strength and Morphology

“…In the PLA/SEBS bioblends there is a shift to the left of the T g and of the double melting peak whereas the onset of T cc remained unchanged, though the peak is broadened, indicating the SEBS dispersed phase does not act as a nucleating agent. On the other hand, Yildiz et al when studying the effect of silicon rubber (SR) on the toughening of PLA observed that SR decreased the T cc onset and peak temperature and broadened the T cc peak, acting as a nucleating agent. After thermal treatment (Figure b) there is a disappearing of the T cc of neat PLA and of PLA in the bioblends.…”