MULTIPHASE MATERIALS WITH LIGNIN .12. BLENDS OF POLY(VINYL CHLORIDE) WITH LIGNIN CAPROLACTONE COPOLYMERS

A previously described starlike copolymer consisting of a lignin deriv ative (hydroxypropyl lignin) and caprolactone has been blended with po ly(vinyl chloride) (PVC) over a composition range of 0-100%. Solvent-c ast films of the blends were examined with regard to thermal, mechanic al, crystallinity, and morphological characteristics. In addition, the blends were examined with regard to aging effects. The results sugges t that the lignin/caprolactone copolymer forms either a miscible (by t hermal analysis) or a nearly miscible (with phase dimensions in the or der of 10-30 nm) system in which physical properties are modified over a wide range of modulus and elongation. Blends with copolymer content exceeding 50% reveal partial caprolactone crystallinity that increase s with age. Lignin derivative not copolymerized with caprolactone, by contrast, produces macrophase-separated structures with exceedingly po or properties. Lignin caprolactone starlike copolymers are materials i deally suited as plasticizers for PVC. (C) 1994 John Wiley & Sons, Inc .