- Email: [email protected]
Reinforced thermoplastic for satellite TV dishes
vol.
19, No. 9, Page 9
APPLICATIONS REINFORCED THERMOPLASTIC FOR SATELLITE TV DISHES
Lorival, in the U.K. is using glass reinforced polypropylene to compression mould dishes for the Astra satellite which began transmitting Sky TV programmes in February. Following research conducted by Lorival in collaboration with GE Plastics in Warrington it was recommended that the dishes be made from Technopolymers Structures, manufactured by the GE/PPG joint venture company Azdel Inc. and comprising randomly oriented very long glass fibres in a polypropylene matrix. The high glass fibre content of the material limits thermal expansion to a level close to that of aluminium and it has heat deflection temperatures of 165’~. These features are combined with high strength and outstanding toughness - the material has a flexural strength of 160 MPa and unnotched Charpy impact strength of 100 kJ/m. squared. Further details from Lorival Ltd., Little Lever, Bolton, BL3 1AR. (See also MARKETS section).
PROCESSING TWIN-SCREW EXTRUSION COMFXNJNDING OF HIGHLY-FILLED THERMOPLASTICS
This article is based on the text of a paper given at the 1989 It was presented by Fillers Conference in the U.K. "Filpas." M.J. Brenner of Betol Machinery Ltd. and P.R. Hornsby of Brunel University. Emphasis is given in this paper to the suitability of high torque closely intermeshing co-rotating twin screw extruders for the preparation of heavily filled thermoplastics compositions, through consideration of the requirements for effective compounding of filled materials and the assessment of compound quality, particularly in relation to the level of distributive and dispersive mixing achieved. Examples of thermoplastics compounds containing high levels of filler addition, taken from both laboratory and industrial experience, are reviewed to illustrate these concepts. Attainment of optimum performance from heavily filled thermoplastics compositions, requires the controlled interaction of specific machine design and operating parameters during the compounding process. In closely intermeshing co-rotating twin screw extrusion compounding this can be achieved by combining a series of functional steps, their precise role depending on the form of additives Cont./......
ADDWIVES FOR POLYMERS
@
1989ElsevierSciencePublisbelr Ltd.,E@and./&W&MBO + 2.20 No part of this publication may bee reproduced. stored in a retrieval system, or transmitted by any form or by any means, electronic, mechanical. photocopying, reccording or otherwise, without the prior permission of the publishers. (Readers in the USA. - please see special regulations listed on back cover.)
19, No. 9, Page 9
APPLICATIONS REINFORCED THERMOPLASTIC FOR SATELLITE TV DISHES
Lorival, in the U.K. is using glass reinforced polypropylene to compression mould dishes for the Astra satellite which began transmitting Sky TV programmes in February. Following research conducted by Lorival in collaboration with GE Plastics in Warrington it was recommended that the dishes be made from Technopolymers Structures, manufactured by the GE/PPG joint venture company Azdel Inc. and comprising randomly oriented very long glass fibres in a polypropylene matrix. The high glass fibre content of the material limits thermal expansion to a level close to that of aluminium and it has heat deflection temperatures of 165’~. These features are combined with high strength and outstanding toughness - the material has a flexural strength of 160 MPa and unnotched Charpy impact strength of 100 kJ/m. squared. Further details from Lorival Ltd., Little Lever, Bolton, BL3 1AR. (See also MARKETS section).
PROCESSING TWIN-SCREW EXTRUSION COMFXNJNDING OF HIGHLY-FILLED THERMOPLASTICS
This article is based on the text of a paper given at the 1989 It was presented by Fillers Conference in the U.K. "Filpas." M.J. Brenner of Betol Machinery Ltd. and P.R. Hornsby of Brunel University. Emphasis is given in this paper to the suitability of high torque closely intermeshing co-rotating twin screw extruders for the preparation of heavily filled thermoplastics compositions, through consideration of the requirements for effective compounding of filled materials and the assessment of compound quality, particularly in relation to the level of distributive and dispersive mixing achieved. Examples of thermoplastics compounds containing high levels of filler addition, taken from both laboratory and industrial experience, are reviewed to illustrate these concepts. Attainment of optimum performance from heavily filled thermoplastics compositions, requires the controlled interaction of specific machine design and operating parameters during the compounding process. In closely intermeshing co-rotating twin screw extrusion compounding this can be achieved by combining a series of functional steps, their precise role depending on the form of additives Cont./......
ADDWIVES FOR POLYMERS
@
1989ElsevierSciencePublisbelr Ltd.,E@and./&W&MBO + 2.20 No part of this publication may bee reproduced. stored in a retrieval system, or transmitted by any form or by any means, electronic, mechanical. photocopying, reccording or otherwise, without the prior permission of the publishers. (Readers in the USA. - please see special regulations listed on back cover.)