The results showed that temperature of freezing storage had influences on the zein films, which led to the changes of mechanical properties, equilibrium moisture content (EMC), water vapor permeability (WVP).

The effect of zein films and zein films plasticized with 3 % oleic acid(OA-zein films) on biodegradability and water vapor permeability(WVP) is researched.

Properties tensile strength,water vapor permeability,gas permeability and folded trace of the film were analyzed, which shows that they are related to the contents of chitosan and stearic acid and the condition when films were prepared.

,the water vapour transmissionthrough the cold insulation materials.

The steady-state permeability experiment is the method recommended to be used to determine water vapor transmission rate(WVTR) of polythene(PE),polyvinyl alcohol(PVA) and soy protein isolate(SPI) films at 35%～90% relative humidity(RH) and 10 ℃～40 ℃ gradient.

MOCON PERMATRAN-W and MOCON OX-TRAN were used to determine water vapor transmission rate(WVTR) and oxygen transmission rate(OTR) of polyvinyl alcohol(PVA) films at 35%～90% relative humidity gradient.

The polystyrene foam plastics is one of the most widespread materials of applying in external insulation outside wall system,water vapor permeability coefficient affects its heat conduction performance and aging resistance performance,but test methods of the coefficient in its product standards aren t suitable for the test and the conclusion evaluation of this material.