In situ fibre-reinforced composite films of poly(lactic acid)/low-density polyethylene blends: effects of composition on morphology, transport and mechanical properties

Abstract

This study aimed to investigate the effects of blend composition on packaging-related properties of poly(lactic acid) (PLA) and low density polyethylene (LDPE) blown films. Blend films with PLA contents of 5-20 wt% were produced and compared. Scanning electron micrographs of cross-sectional cryofractured surfaces of the blend films revealed that in situ fibre-reinforced composites were obtained. Viscosity ratio of the polymer components of ca 1 confirmed that fibre formation was favourable for this blend system. PLA microdomains were dispersed throughout the film in forms of long fibres (length-to-diameter ratio > 100) and ribbons. The number of fibres and ribbons increased with an increase of PLA content. Critical content of PLA was found to be 20 wt% for effective improvement of both moduli and gas barrier properties. Incorporation of poly[ethylene-co-(methyl acrylate)] compatibilizer showed minimal effect on PLA structure. However, it did improve moduli and O 2 barrier properties when sufficient amount (1.5 pph) was used in 10 wt% PLA/LDPE. In short, flow behaviour, ratio of polymer components and degree of compatibility together played intricate roles in the morphology and hence mechanical and transport properties of PLA/LDPE immiscible blends.where c is the percentage crystallinity in the sample, ΔH m is the melt enthalpy (J g −1 ) and ΔH ∞ is the melt enthalpy of a spherulite

Effect of different compatibilizers on environmentally friendly composites from poly(lactic acid) and diatomaceous earth

“…Biopolymers, besides being respectful to the environment, minimize the carbon footprint and represent high environmental efficiency materials for industry. One of the most used biopolymers is poly(lactic acid) (PLA) . PLA is an aliphatic polyester obtained from the bacterial fermentation of vegetable biomass, rich in starch such as corn, wheat, sugar cane etc …”

“…One of the most used biopolymers is poly(lactic acid) (PLA). 6 PLA is an aliphatic polyester obtained from the bacterial fermentation of vegetable biomass, rich in starch such as corn, wheat, sugar cane etc. 7 The functional properties of some biopolymers can be improved by the incorporation of particles, which has led to the so-called biocomposites.…”

Production and investigation of structure and properties of polyethylene–polylactide composites

“…In literature, there are some works on production and investigation of the composites based on PLA and polyethylene . These works are mainly dedicated to the study of the composition effect on the rheological and mechanical properties of the systems under investigation.…”

“…In literature, there are some works on production and investigation of the composites based on PLA and polyethylene. [13][14][15][16][17][18][19][20] These works are mainly dedicated to the study of the composition effect on the rheological and mechanical properties of the systems under investigation. The incompatibility of these polymers was demonstrated 19 via investigation of the morphology of the composites by scanning electron microscopy (SEM) method.…”

In Focus Emerging Polymer Technologies Summit (EPTS'16)

“…In addition, the Summit included many other keynote and invited speakers, and a raft of young and early career scientists' contributions that formed an integral part of the EPTS'16 scientific program. This In Focus comprises five papers . Unfortunately, many of the speakers did not elect to take advantage of this special In Focus, however, note that Professor Moad's plenary presentation (Co)polymerization of the conjugated diene monomers: butadiene, isoprene and chloroprene has already been published in Polymer International …”