Viscoelastic properties and extrusion processability of poly(vinyl butyral)

Abstract

Rheological properties and flow instability at capillary extrusion of a random terpolymer composed of vinyl butyral, vinyl alcohol, and vinyl acetate, that is denoted as PVB in this article, are studied. It is found that the rubbery plateau modulus G 0 N is 1.3 MPa at 100 C from the oscillatory shear modulus. Furthermore, the average molecular weight between entanglement couplings M e is found to be 2670. Because of the relatively high value of G 0 N , it shows rubbery region in the wide temperature range (90 C-180 C). At the capillary extrusion, the surface instability (shark-skin failure) appears prior to volumetric melt fracture. The onset stress of the shark-skin failure, ca. 0.18 MPa, is similar to that of polyethylene, although PVB used in this study has narrow molecular weight distribution. Moreover, the apparent slippage is not detected, presumably due to good adhesion to the die wall. V C 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40337.

Autonomic self‐healing of poly(vinyl butyral)

“…Furthermore, the sample has no crystalline phase with T g of 76°C, which were evaluated by DSC measurements at 10°C/min. Other basic characterizations were performed in our previous article …”

“…Other basic characterizations were performed in our previous article. 38 After being dried, PVB was compressed into flat sheets with various thicknesses by a compression-molding machine (Tester Sangyo, Japan, Table-type test-press) at 190 C under 10 MPa for 3 min. Then, the samples were rapidly cooled down in an ice-water bath.…”

Design of thermochromic polymer blends containing low‐mass compounds

“…In industry, the interlayer comprises either a terpolymer of vinyl butyral, vinyl alcohol, and vinyl acetate (conventionally called PVB) or a copolymer of ethylene and vinyl acetate (EVA). PVB is an amorphous polymer with a glass transition temperature ( T g ) of approximately 80 °C . The EVA that is used for laminated glass has a high vinyl acetate content and a low degree of crystallinity; it therefore has high transparency .…”

“…PVB is an amorphous polymer with a glass transition temperature (T g ) of approximately 80 8C. 1,2 The EVA that is used for laminated glass has a high vinyl acetate content and a low degree of crystallinity; it therefore has high transparency. 3 A plasticizer is usually added to both polymers when they are used for the interlayer of laminated glass to increase the adhesive strength with the glass.…”

Comparative Analysis of the Effect of Organoclay, Boron Nitride, and Fluoropolymer on the Rheology and Instabilities in the Extrusion of High Density Polyethylene

“…The major challenge during extrusion is the onset of melt instabilities that hinder high productivity [1][2][3][4]. Processing aids are often added to polyolefins during their extrusion to make the processes economically viable.…”