Effects of Polyol-Based Plasticizer Types and Concentration on the Properties of Polyvinyl Alcohol and Casein Blend Films


Ucpinar Durmaz B., AYTAÇ A.

JOURNAL OF POLYMERS AND THE ENVIRONMENT, vol.29, no.1, pp.313-322, 2021 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 29 Issue: 1
  • Publication Date: 2021
  • Doi Number: 10.1007/s10924-020-01881-x
  • Journal Name: JOURNAL OF POLYMERS AND THE ENVIRONMENT
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Aerospace Database, BIOSIS, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, Environment Index, Geobase, Greenfile, Metadex, Pollution Abstracts, Civil Engineering Abstracts
  • Page Numbers: pp.313-322
  • Keywords: Polyvinyl alcohol, Casein, Plasticization, Poly(ethylene glycol), Sorbitol, BARRIER PROPERTIES, MECHANICAL-PROPERTIES, PHYSICAL-PROPERTIES, EDIBLE FILM, GUM, GLYCEROL, SORBITOL, GELATIN
  • Kocaeli University Affiliated: Yes

Abstract

This study aimed to examine the structural, mechanical, thermal and barrier properties of the polyvinyl alcohol/casein (PVA/CA) films plasticized with poly(ethylene glycol) (PEG) and sorbitol (SOR). The films were prepared by solution casting technique at different loading levels of plasticizers (10-15-20-25%). The mechanical results indicated that PEG and SOR effectively plasticize the PVA/CA film while SOR efficiency was higher than PEG. The addition of plasticizers decreased the tensile strength while the increased elongation at break value of PVA/CA film. The maximum tensile strength was observed in 10% PEG addition as 37.5 MPa. On the other hand, maximum elongation at break value was observed in 15% SOR at 369% that was higher than the un-plasticized film about 58%. The water contact angle measurements showed that all films were hydrophilic structures (32-75 degrees). Also, the water vapour permeability of the un-plasticized film was measured as 6.4 g m(-1) s(-1) Pa-1 x 10(-11). This value decreased with the addition of PEG (5.5 g m(-1) s(-1) Pa-1 x 10(-11)) while increasing SOR addition (12.2 g m(-1) s(-1) Pa-1 x 10(-11)). The thermal degradation temperature of un-plasticized PVA/CA film was decreased with plasticization. The residual weight of un-plasticized PVA/CA was 12.5 wt. %, which decreased at 4.5 wt. % for PEG-25 and 4.8 wt. % for SOR-20 films. Also, the melting temperature of the films decreased by increasing the content of plasticizers. Melting temperatures of SOR containing films were lower than PEG containing the films. Consequently, un-plasticized and plasticized PVA/CA-based films successfully prepared and analyzed to determine the appropriate plasticizer. All prepared films exhibited acceptable properties for use as food packaging or biobased materials.