Effect of polyethylene glycol on the crystallization and impact properties of polylactide‐based blends

Abstract

Polylactide (PLA) was plasticized by polyethylene glycols (PEGs) with five different molecular weights (M w = 200-20,000 g/mol). The effects of content and molecular weight of PEG on the crystallization and impact properties of PLA were studied by wide-angle X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, transmission electron microscopy, and V-notched impact tests, respectively. The results revealed that PEG-10,000 could significantly improve the crystallization capacity and impact toughness of PLA. When the PEG-10,000 content ranged from 0 to 20 wt%, the increases in both V-notched Izod and Charpy impact strengths of PLA/PEG-10,000 blends were 206.10% and 137.25%, respectively. Meanwhile, the crystallinity of PLA/PEG-10,000 blends increased from 3.95% to 43.42%. For 10 wt% PEG content, the crystallization and impact properties of PLA/PEG blends mainly depended upon PEG molecular weight. With increasing the M w of PEG, the crystallinity and impact strength of PLA/PEG blends first decreased and then increased. The introduction of PEG reduced the intermolecular force and enhanced the mobility of PLA chains, thus improving the crystallization capacity and flexibility of PLA.

The effects of processing parameters on the morphology of PLA/PEG melt electrospun fibers

“…In this regard, we have previously succeeded in melt electrospinning of PLA into ultrafine fibers with a custom‐built device, by incorporating polyethylene glycol (PEG) as a viscosity reducing agent . It is notable that PEG, which is a hydrophilic semicrystalline and biodegradable polymer, is considered an effective plasticizer for PLA‐based systems . PLA/PEG blends with improved cell affinity, biodegradability as well as physical and mechanical properties are good candidates for both industrial and biomedical applications.…”

Mechanical and flame retardant properties of polylactide composites with hyperbranched polymers

“…2, the DSC thermogram indicates a glass transition temperature (T g ) at 58 C for pure PLA. The peak temperature of cold crystallization was approximately 119 C, and there were two melting peaks that appeared at 152 and 158 C, which could result from either a crystal transition from the a 0 to a-form during heating or a lamellar reorganization [3,20]. With an addition of 30 wt% ATH, the T g increased to approximately 62 C, and the cold crystallization temperature was reduced to 115 C, which could be attributed to the interaction between ATH and PLA.…”

The effect of poly(ethylene glycol) mixed with poly(l‐lactic acid) on the crystallization characteristics and properties of their blends

“…Among the thermoplastic aliphatic polyesters, poly( l ‐lactic acid) (PLLA) presents excellent biodegradability, biocompatibility and bioresorbability along with transparency and low toxicity . Standard‐grade PLLA is also characterized by high modulus and strength but is brittle and rigid in nature with poor toughness and low melt strength which lead to difficulties in demoulding .…”

“…focused on plasticizing amorphous poly[( l ‐lactide)‐ co ‐( d , l ‐lactide)] with four different commercially available adipates, in order to enhance its mechanical and thermal properties. One of the most promising candidates widely used in the plastics industry to improve processability and ductility of semicrystalline polymers is poly(ethylene glycol) (PEG) . PEG is a linear or branched hydroxyl‐terminated polyether, which is usually prepared by anionic ring‐opening polymerization of ethylene oxide .…”