Humidity and scaning rate effects on the glass t ransition ( Tg) of ABS (acrylonitr ili butadiene styrene)

Acrylonitrile-butadiene-styrene terp olymer is a high performance th ermoplastic containing two a morphous phases; a rubbery phase provide d by buta diene, and a strength- lending sty rene- a crylonitrile (SAN) copolymer two -component phase. It has two glass transitions. The low temperature glass transition is due t o the butadi ene phase, and the high temperature one is due to the SAN phase [۱]. Glass transition is a physical property of an amorph ous material that define s the c hange from an iso-visc ous glassy state to a rubbery state (a nd vice versa) at a tem perature, which is referred to as the glass transition te mperature, T g [۲]. According to pre vious research, the influence o f scan rates and molecular weigh t (۹۰۰ to ۱ .۸ l۰۶) on the glass transition te mperature of low p olydispersit y polystyre ne has been studied by DSC at different heating rates [۳]. The effect of water o bserved on the extent of physical ageing is rel ated to the plasticizing effect of water on Tg [۴ ]. Our a im was to in vestigate the effect of scan rate and humidity on the glass transition te mperature of ABS p olymer via differential scanning calo rimetry (DSC).

کلیدواژه ها:

acrylonitril butadiene styrene (A BS) ، glass transition (Tg) ، diffe rential scanning c alorimetry ( DSC)