Polymer, Vol.38, No.22, 5551-5555, 1997
Drawing of Sprayed Poly(Vinyl Alcohol) Films
By spraying PVA aqueous solutions, precursor films were prepared. The spray-dried PVA films have higher drawability than solution-cast PVA films. This phenomenon comes from the structure of the sprayed PVA film. The sprayed PVA films are comprised of stacked polymer particles which coalesce during drying. The ease of H-bond formation between precipitated particles made the precursor film tough. During drawing the structure changed to a fibrillar structure. The modulus and strength of the drawn sprayed PVA films are about half of those of the drawn solution-cast PVA films.