preparation and investigation of mechanical properties and optical clarity of polyvinylbutyral film

polyvinyl butyral (pvb) was synthesized by condensation reaction of polyvinyl alcohol (pva) with butanal in aqueous medium containing an effective emulsifier and an inorganic acid as catalyst. the product was characterized by, ir, tg and dtg techniques. percentage of vinyl alcohol groups in the pvb was determined by a chemical method according to a standard method. some clear and soft film samples containing the pvb and some high boiling point plasticizers were made by hot press. for this purpose plasticizers such as bis(2-ethylhexyl)phthalate (dop) and bis(2-ethylhexyl) terephthalate (dotp) were purchased and the triethylene glycol bis(2-ethylhexanoate) (tegb) was synthesized. the film samples containing 30 percent mixture of triethylene glycol bis(2-ethylhexanoate) and bis (2-ethylhexyl)phthalate with ratio 65/35 showed some improved mechanical and optical properties.