Properties of high molecular weight polycarbonate synthesized by using the solid phase polymerization method

• Published in: KOBUNSHI RONBUNSHU Vol. 57; no. 1; pp. 15 - 22
• Main Authors: HACHIYA, Hiroshi, YOSHIDA, Kazuyuki, YONEDA, Haruyuki, MATSUDA, Yuko, TAKEDA, Kunihiko
• Format: Journal Article
• Language: Japanese
• Published: Tokyo The Society of Polymer Science, Japan 01.01.2000; Tsukiji daisan nagaoka
• Subjects: Exhausted Gas; Hydrolysis; Polycarbonate; Polyvinyl butyral; Solid State Polymerization; Ultra High Molecular Weight
• ISSN: 0386-2186; 1881-5685
• DOI: 10.1295/koron.57.15

Properties of high molecular weight polycarbonates (PC) having average molecular weights (Mw) of 52, 200-97, 060 synthesized by using the solid phase polymerization method which the authors developed have been studied. The melt viscosity of PC having Mw 52900 is 64, 300 poise at 300t. It is much higher than that of 28, 800. But the viscosity decreases to 13600 poise and this is a limit of molding any applications at 350°C. In comparing mechanical characteristics of molecular weight 97060 with 27500, HDT rises by 7°C and tensile strength, flexural strength, flexural modulus, and Izod impact strength decrease respectively by 5%, 8%, 5%, and 40%. There was no merit to increase of molecular weight in the mechanical characteristics. However the high molecular weight polycarbonates have excellent properties in abrasion resistance, hydrolysis resistance, and solvent resistance. PC having Mw 54100 had transparency after 400 hrs exposing in 120°C steam, and had about eight times smaller thrust abrasion weight loss compared with Mw 35100. Moreover, when laminating with polyvinyl butyral which became a cloudy polycarbonate having Mw 35100, cloudiness was not seen atall as for the high molecular weight polycarbonate having 52200 Mw. The high molecular weight polycarbonate synthe sized by the solid phase polymerization has the possibility to expand the range of the application of polycarbonate.