Oxygen barrier films based on low-density polyethylene/ ethylenevinyl alcohol/ polyethylene-grafted-maleica as a compatibilizer

In this research, high oxygen barrier films were organized based on low-density polyethylene (LDPE)/ ethylene vinyl alcohol(EVOH)/ polyethylene-grafted-maleic anhydride (LDPE-g-MA) as a compatibilizer. The effects of EVOH (10–30 wt. %) andLDPE-g-MA (0–10 wt. %) levels on the properties of final films were evaluated. The morphology of specimens was observed byusing scanning electron microscopy (SEM). Oxygen transfer rate (OTR) results revealed that the addition of EVOH up to 30 wt.% to neat LDPE can significantly decrease oxygen permeability. LDPE-g-MA increased permeability so the amount ofcompatibilizer must be fine-tuned based on the EVOH level in different samples. The experimental results revealed that theaddition of 30 wt. % EVOH, and 0 wt. % LDPE-g-MA to the LDPE matrix gave the best oxygen barrier properties. Elasticmodulus and tensile strength increased with introducing of EVOH and LDPE-g-MA to the polyethylene matrix. On the otherhand elongation at break decreased with the addition of EVOH and augmented with introducing of compatibilizer to the samples.Incorporation of EVOH and LDPE-g-MA to the LDPE matrix and increasing the amount of these components in the samples ledto higher storage modulus and zero shear rate viscosity, but, lowered the frequency of intersection point of storage modulus (G )and loss modulus (G ). The only exception was that in the samples without compatibilizer increasing the level of EVOH resultedin a lower zero shear rate viscosity and higher frequency of intersection point of G and G .

Keywords:

Polymer blends and alloys , barrier , compatibilizer , oxygen permeability , polyethylene