Thermoplastic starch–polyethylene blends homogenised using deep eutectic solvents

Abstract

Polyolefin based plastics are extensively used for packaging applications and as such they tend to have a short service life but they have a long environmental persistence. One strategy to accelerate the mechanical degradation of polyolefin plastics in the environment is to blend them with carbohydrate based polymers. Unfortunately polyolefins are hydrophobic whereas carbohydrates tend to be hydrophilic so the two do not blend without chemical modification of the carbohydrate. In this study high density polyethylene, HDPE and thermoplastic starch, TPS are used as the polymers with deep eutectic solvents, DESs as the modifiers. Both TPS and DESs are biodegradable and the DESs are water miscible and biocompatible ensuring that the composite plastic contains a biodegradable flaw which should enable mechanical and chemical degradation. It is shown that DESs enable facile mixing of the two polymers. The composite has a strength similar to TPS but a ductility greater than either of the two components. The glass transition temperature of the composite plastic shows that they are homogeneously mixed and data suggests that the DESs act as lubricants rather than plasticisers. Fig. 6 Mechanical analysis of m-HDPE:TPS blends (BBbefore boiling and ABafter boiling) (a) UTS (b) elongation at break (c) stress-strain curves.This journal is

Globular and Fibrous Proteins Modified with Deep Eutectic Solvents: Materials for Drug Delivery

“…The low values for elongation at break suggest that the DES does not penetrate well into the globular structure of the protein and acts more like a lubricant than a plasticizer. A similar behavior was observed for DESs added to high-density polyethylene (HDPE) where interaction with the chain was minimal and the DES showed solubility < 3 wt% and this had negligible effect on the glass transition temperature or the UTS [14]. The inability of the DES to penetrate into the zein structure is possibly because the protein is relatively hydrophobic and may explain why the fatty acids and PEG acts as better plasticizers for zein than the polyols [8].…”

Polymer Science and Engineering Using Deep Eutectic Solvents

“…More interestingly, the DES modified-HDPE was blended with starch plasticized with DES. DES-modifications allowed to blend, for the first time, polyolefins (HDPE) to nonchemically modified carbohydrates (starch) [115].…”

Deep Eutectic Solvents for Starch Treatment

“…Abbott et al [44] used the DES to homogenize a polyethylene/starch blend. The first step was a modification of PE with a DES based on choline chloride with the following different HBDs: urea, glycerol, and ethylene glycol.…”