Further studies of polycarbonate‐poly(butylene terephthalate) blends

Abstract

The mechanical properties (tensile strength, low temperature falling weight impact strength) of XENOY CL‐100 (a blend of polycarbonate and polybutylene terephthalate) have been studied. This blend is comprised of tough components and the property combinations that result may be useful for certain applications. The hydrolysis resistance of the blend in deionised water at 40°C has been studied. After 30 weeks it did not lose its tensile strength, but subsequently it did lose 50% of the low temperature (−70°C) falling weight impact strength. If the −70°C low temperature toughness is an important quality, this should be taken into account. However, the low temperature (−70°C) falling weight impact strength of pure polycarbonate and of pure poly(butylene terephthalate) is very low, whilst XENOY CL‐100 is still tough material, even after 30 weeks immersion at 40°C. Further study of the composition of XENOY CL‐100 showed that this blend is composed of polycarbonate. poly(butylene terephthalate) and crosslinked acrylic rubber; traces of titanium‐catalyst residue for the poly(butylene terephthalate) polymeristaion and black dye have also been found.

Phase behavior of ternary PBT–PC/phenoxy blends

“…Among condensation polymers both bisphenol A polycarbonate ( PC ) [12][13][14][15][16][17][18][19][20][21][22][23][24][25] and poly ( hydroxy ether of bisphenol A) ( p h e n~x y )~~-~~ have been widely studied as components of binary polymer blends. However, despite the potential miscibility of phenoxy with polyesters or related materials, the PC /phenoxy blend is not fully miscible,34 although a favorable balance of properties can be produced in this blend through interchange reactions in the melt state.…”

“…However, despite the potential miscibility of phenoxy with polyesters or related materials, the PC /phenoxy blend is not fully miscible,34 although a favorable balance of properties can be produced in this blend through interchange reactions in the melt state. 35736 If we look at the possibility of combining PC/ phenoxy blends with a third component, we realize, first, that PBT is fully miscible with phenoxy, second, that a partially miscible PC/PBT blend with a PBT content of 44% l 3 (Xenoy CL General Electric) has been commercialized, and, finally, that studies have been done of the binary blends PC/ PBT, [12][13][14][15][16][17][18][19][20]33,37,38 P B T / p h e n~x y ,~~,~~ and PC/phenoxy.34-36 Moreover, PC, in spite of its high ductility, stability, and outstanding impact resistance, has a high melt viscosity and poor hydrolysis resistance.…”