ABOUT INDEXING EDITORIAL BOARD ARCHIVES AUTHOR GUIDELINES SUBMIT PAPER NEWS, EVENTS AUTHOR'S PAGE CONTACT
Materiale Plastice
Cite as: Mater. Plast.
https://doi.org/10.37358/Mat.Plast.1964

OSIM Nr. R102356
ISSN Print 0025-5289
ISSN Online 2668-8220
Materiale Plastice - Latest Issue

Latest Issue >>>
ARCHIVES
   Volume 61, 2024
   Volume 60, 2023
   Volume 59, 2022
   Volume 58, 2021
   Volume 57, 2020
   Volume 56, 2019
   Volume 55, 2018
   Volume 54, 2017
   Volume 53, 2016
   Volume 52, 2015
   Volume 51, 2014
   Volume 50, 2013
   Volume 49, 2012
   Volume 48, 2011
   Volume 47, 2010
   Volume 46, 2009
   Volume 45, 2008
   Volume 44, 2007
   Volume 43, 2006
   Volume 42, 2005
   Volume 41, 2004
   Volume 40, 2003
 
<<<< back

Materiale Plastice (Mater. Plast.), Year 2007, Volume 44, Issue 3,





Rheological Behaviour of Some Biodegradable Composites with Poly(vinil Alcohol) and Starch


Abstract:
The study presents rheological behaviour of some solution mixtures from poly(vinyl alcohol) (PVA) and starch in water, with addition of glycerol as plasticizer and urea (nitrogen source for microorganisms). These solutions were used to obtained biodegradable films. The effect of temperature and concentration on the rheological behaviour of poly(vinyl alcohol) and starch solutions in water, was studied in the temperature range of 20-60 0C and concentration 10-20 % at different gravimetrical ratio PVA/starch (3.00, 1.66, 1.00, 0.60, 0.33). The rheological behaviour was studied to gradient of shear rate which varied between 3 and 1310 s-1. From experimental data it was established that concentrated solutions of PVA/starch blends exhibit a non-newtonian rheological behaviour of pseudoplastic type. The flow activation energies versus temperature are situated in range of 11.86-49.92 kJ/mol, while against the concentration between 1.61-4.54 kJ/mol. The consistency index increased with decrease of temperature and recording great values in the concentrated solutions case. The solutions with PVA/starch subunitar gravimetrical ratio have great values of consistency index, to compare those with supraunitar ratio. This fact shows that the starch is the polymer which confers solutions a great viscosity, but low temperatures determines even their jellification. Keywords: biodegradable materials, rheological behaviour, poly(vinyl alcohol), starch



Issue: 2007 Volume 44, Issue 3
Pages:
download pdf   Download Pdf Article
Creative Commons License
This article is published under the Creative Commons Attribution 4.0 International License


Downloads number: 0
<<<< back
 
  Search Authors
Crossref Member Badge
 DOI  logo
 Gold Open Access | Source=http://www.plos.org/  | Author=art designer at PLoS
Creative Commons License