Injection‐stretch blow molding of poly (lactic acid)/polybutylene succinate blends for the manufacturing of bottles

Abstract

The stretch blow molding process of plastic preforms is widely used for the manufacturing of bottles in numerous market sectors, with high production volumes and low unit costs. In the sector of alcoholic beverages and, in particular, of wine, plastic bottles are used sporadically. Glass bottles or other economic solutions such as laminated cardboard containers or so-called bagin-boxes are regularly preferred. However, the high ease of use, lightness, recyclability and low cost of plastic materials are the main reasons that are fueling interest especially in wine producers. Poly (ethylene terephthalate) bottles have recently been introduced to the market, although their success has been limited by poor gas impermeability and above all by their recognized high environmental footprint. Barrier can be improved by oxygen scavenger and plasma coating. Environmental footprint is rather low when recycled but that is not well possible with scavenger. Bioplastic materials offer an interesting alternative to fossil-based plastics, combining most of their technical advantages with a lower environmental impact. However, they are more expensive and complex to process. In addition, mechanical and barrier properties are often less than for conventional polymers. In this work, therefore, the development of bioplastic bottles with low gas permeation by stretch blow molding was studied. Poly (lactic acid)-polybutylene succinate blends have been modified by adding additives that obstruct the passage of gaseous molecules through the wall of the bottle. The studies have in particular concerned the extrusion and characterization of bioplastic compounds, the injection molding of preforms, and the blowing of bottles. The results obtained showed that it is possible to obtain low permeation bioplastic bottles, which are an ecological alternative to conventional solutions for packaging.

Tuning the mechanical and thermomechanical properties through the combined effect of crosslinking and annealing in poly(lactic acid)/acrylonitrile‐EPDM‐styrene blends

“…The versatility of PLA applications is attributed to its good mechanical properties, comparable to polystyrene (PS) and polyethylene terephthalate (PET), including high mechanical strength and elastic modulus 15,16 . In addition, PLA can be processed in conventional polymer industry and additive manufacturing equipment 17,18 . However, PLA has drawbacks, including its high brittleness, degradability during processing in the presence of humidity and high temperatures, and low heat deflection temperature 19,20 .…”

“…15,16 In addition, PLA can be processed in conventional polymer industry and additive manufacturing equipment. 17,18 However, PLA has drawbacks, including its high brittleness, degradability during processing in the presence of humidity and high temperatures, and low heat deflection temperature. 19,20 Researchers are trying to improve PLA's mechanical and thermomechanical performance in this context, primarily through polymer blends.…”

Effect of addition of triallyl isocyanurate and post‐ultraviolet irradiation on the selected properties of composites of poly(lactic acid), poly(butylene succinate) and nano‐sized calcium carbonate

“…It is an ideal polyester for PLA modification because it toughens PLA while maintaining its own strength and improving PLA crystalline properties. [13][14][15][16] However, PLA and PBS have incompatible two-phase thermodynamics and small interface bonding, and PBS has excessive size when used as a dispersed phase size, which lead to no significant improvement in the overall properties of the resulting blends. In view of this, improving the compatibility of the blends and ensuring good PBS dispersion are particularly important to improve the performance of the blends.…”

“…PBS has good impact strength and high elongation at break. It is an ideal polyester for PLA modification because it toughens PLA while maintaining its own strength and improving PLA crystalline properties 13–16 . However, PLA and PBS have incompatible two‐phase thermodynamics and small interface bonding, and PBS has excessive size when used as a dispersed phase size, which lead to no significant improvement in the overall properties of the resulting blends.…”