Effects of plasticizers and emulsifiers on mechanical properties of konjac glucomannan / ethyl cellulose blend films

The impacts of the addition of different plasticizers and emulsifiers on mechanical properties of konjac glucomannan / ethyl cellulose( KE) blend films,and the mechanisms were mainly investigated in this study. Results indicated that the film had a first increase and later a decrease on tensile strength( TS)( p < 0.05),and a first decrease but later increase trend on elongation ratio at breaking( EAB),with increased addition( 5% ～35%,w / w)of plasticizers( dibutyl sebacate,epoxidized soybean oil,and triethyl citrate). The addition( 0.1% ～ 0.9%,w / w) of emulsifiers( span 80,sucrose fatty acid ester,and Tween 80) did not show significant impact on TS of KE film,but would lead to a first increase and later a decrease on EAB( p < 0.05).The TS of the blend film reached to 82.37 MPa when 20% dibutyl sebacate was addicted,as the EAB reached to 19.78% when 0.7% span 80 was addicted.Based on these results,a hypothesis model was proposed and an assumption of the mechanisms of plasticizers' and emulsifiers' impact on KE film was made.