- Email: [email protected]
RP takes leap into high risers
Reinforced plastics in chemical plant
RP takes leap into high risers
Hall, A. F. Rein[orced Plastics, Vol
Modern Plastics International, Vol 1, No 3, pp 5°-53 (March 1971)
15, No 5, p 98 (May 1971) In this review article the requirements of materials in chemical plant are considered and the reasons for the current interest in asbestos reinforced phenol - formaldehyde, resorcinol formaldehyde and furane resins and glass-fibre-rein.forced epoxide and polyester resins become apparent. T h e r e arc interesting sections on the philosophy of design in these materials and on production and economics of their use chemical environments.
(7114155)
The significance of the rubber damping peak in rubber modified polymers properties
Keskkula, H., Turley, S. G. and Boyer,
Shephard, R. F.
R. F. Journal oJ Applied Polymer Science, Vol 15, No 2, p 351 (February 1971)
Reinforced polypropylene; and prospects
Harrison,
This note contains details of an l 1storey office building built with glassreinforced polyester panels used for exterior walls at about half the cost of a precast concrete curtain wall. These moulded panels are deeply recessed to take high velocity wind loads, but will take no lateral or vertical loads. Fire resistance, non-fade colouring and economics make these panels extremely attractive. (71/4/59)
P. and
Plastics and Polymers, Vol 39, No 140, pp 103-110 (April 1971) Filled and reinforced grades of polypropylene are already quite widely used where high modulus, high strength, creep resistant plastic is required. T h e filler is usually talc, asbestos or glass. Talc is least effective but very inexpensive. Asbestos is well established in the USA and glass has been limited by its poor adhesion to polypropylene. Recently, modified glass fibres have now made low cost high quality glass reinforced polypropylene available and this material is expected to compete with pressure die-cast metals. (71/4/56) Reinforced thermoforms succeed in many markets
Modern Plastics International, Vol 1, No '2, pp 14-16 (February 1971) Sheets of thermoplastics rigidized with .glass-fibre/polyester backing are findlng increasing applications and designers are most impressed with the versatility of these materials. T h e advantage of thermoforming of polypropylene, Pvc, polyethylene and chlorinated Pvc is coupled with the stiffness of the reinforced backing, applied later. In these composites high bond strengths can be obtained between the two components because of the similarity in expansion characteristics. T h e main current applications are in chemical process equipment and sanitary ware. ( 7 1 / 4 / 57) RP heads for mass production
Wood, A. S. Modern Plastics Inter-
national, Vol 1, No 2, pp 38-4° (February 1971) T w o major factors have led to an anticipated surge of reinforced plastics into mass production. T h e first is a result of advances in resin technology and improvement in reinforcement materials and the second is .the advance in processing of Re ingredients. Thi~ state of affairs has already led to a breakthrough into the market for automobile components and production of Re components in the 200 000 to 400 000 range is a reality. Forecasts predict a 1976 consumptioh level of 2'7 billion pounds in the US alone. (71/4/58)
T h e dynamic shear modulus and mechanical damping capacity of rubber modified rigid polymers are correlated with the concentration of rubber present and the impact strength of the composites. It is suggested that the damping peak does not have the wide significance it has hitherto been thought to have since its size, shape and position on the temperature axis are affected by composition, morphology and the method of polymer preparation. (71/4/60) Some opportunities for development in therm.plastie paper and paper replacements
Benjamin, C. and Vinty, M. J. Plastics and Polymers, Vol 39, No 13~, pp 64-76 (l~ebruary 1971) T h e cost trends of paper and plastics make the use of the latter material in packaging and communications very favourable. Cellulose fibres and plastics may be combined to give properties unobtainable by the use of either material alone. Technologies by which this can be achieved are outlined and a considerable amount of data on properties, applications and consumption is given. (71/4/61) Strength and fracture toughness of carbon fibre polyester composites
Harris, B., Beaumont, P. W.. R. and Moncunill de Ferran, E. Journal o[
Materials Science, Vol 6, No 3, pp 938-951 (March 1971)
A study of fracture behaviour of carbon-fibre/polyester composites dur. ing mechanical testing has been carried out on the scanning electron microscope. Several surface treatments were carried out on the fibres to obtain a range of composite interlaminar shear strengths and an attempt was made to correlate this parameter with composite work of fracture using a charpy impact test, a drop-weight test and a slow-bend test. T h e effect of moisture on toughness was also studied. It is concluded that improving fibre-resin bonding tends to increase brittleness and that contributions to work of fracture from the matrix and pulling fibres from the matrix against friction are in the ratio 1:4. (71/4/62)
The strength and stiffness of polymers
Frank, F. C. Proceedings o] the Royal
Society (Series A), Vol 319, p 127 (1970) It is contended that polymers may be thought of as intrinsically composite materials even though they are chemically homogeneous since fully aligned long chain polymers would have a Young's modulus in the alignment direction similar to that of steel. It is envisaged that more steps will be made to control the volume fraction of aligned chains in order to achieve desired combinations of strength and toughness even though fabrication costs are likely to be greater. ( 7 1 / 4 / 63)
Stress/strain behaviour of SAN/glass bead composites above the glass transition temperature
Narkis, M. and Nicolais, L. Journal
o[ Applied Polymer Science, Vol 15, No 2, p 469 (Febraary 1971) Stress/strain and stress/relaxation behaviour of saN/glass-bead composites above the glass transition temperature were studied and it was found that relaxation data for the filled polymer, which is independent of strain, may be calculated by the multiplication of the relaxation modulus ( l + e p ) where ep is the matrix strain, By plotting tensile stress against ep, stress/strain curves at constant strain rate for different concentrations of filler may be moved to forin a general curve, which is independent of filler content. (71/4/64)
Tensile fracture of graphite reinforced epoxy composites
fibre
Berg, C. A., Rinskv, A. Fibre Science and Technology, Vol 3, No 4, p 295 (April 1971) T h e use of high speed photography has revealed that the shattering of carbon-fibre/resin composites in tension is due to internal wave reflection after the transverse crack has passed across the specimen, and not ta dynamic crack branching. T h e longitudinal cracks which cause shattering are shown to initiate inside the specimen at points well removed from the path of the main tensile crack which runs normal to the fibre axis. (71/4/65)
Viscoelastic characterization of a nonlinear fibre-reinforced plastic
Lou, Y. C. and Schapery, R. A. Journal
of Composite Materials, Vol 5, pp 208234 (April 1971) T h e non-linear, viscoelastic behaviour of unidirectional, glass-fibre/epoxy composite material has been characterized by using isothermal, uniaxial creep and recovery tests togethe~ with a constitutive equation based on thexmodynamic theory. Specimens show an appreciable amount of nonlinearity except under loading parallel
COMPOSITES September 1971
]95
RP takes leap into high risers
Hall, A. F. Rein[orced Plastics, Vol
Modern Plastics International, Vol 1, No 3, pp 5°-53 (March 1971)
15, No 5, p 98 (May 1971) In this review article the requirements of materials in chemical plant are considered and the reasons for the current interest in asbestos reinforced phenol - formaldehyde, resorcinol formaldehyde and furane resins and glass-fibre-rein.forced epoxide and polyester resins become apparent. T h e r e arc interesting sections on the philosophy of design in these materials and on production and economics of their use chemical environments.
(7114155)
The significance of the rubber damping peak in rubber modified polymers properties
Keskkula, H., Turley, S. G. and Boyer,
Shephard, R. F.
R. F. Journal oJ Applied Polymer Science, Vol 15, No 2, p 351 (February 1971)
Reinforced polypropylene; and prospects
Harrison,
This note contains details of an l 1storey office building built with glassreinforced polyester panels used for exterior walls at about half the cost of a precast concrete curtain wall. These moulded panels are deeply recessed to take high velocity wind loads, but will take no lateral or vertical loads. Fire resistance, non-fade colouring and economics make these panels extremely attractive. (71/4/59)
P. and
Plastics and Polymers, Vol 39, No 140, pp 103-110 (April 1971) Filled and reinforced grades of polypropylene are already quite widely used where high modulus, high strength, creep resistant plastic is required. T h e filler is usually talc, asbestos or glass. Talc is least effective but very inexpensive. Asbestos is well established in the USA and glass has been limited by its poor adhesion to polypropylene. Recently, modified glass fibres have now made low cost high quality glass reinforced polypropylene available and this material is expected to compete with pressure die-cast metals. (71/4/56) Reinforced thermoforms succeed in many markets
Modern Plastics International, Vol 1, No '2, pp 14-16 (February 1971) Sheets of thermoplastics rigidized with .glass-fibre/polyester backing are findlng increasing applications and designers are most impressed with the versatility of these materials. T h e advantage of thermoforming of polypropylene, Pvc, polyethylene and chlorinated Pvc is coupled with the stiffness of the reinforced backing, applied later. In these composites high bond strengths can be obtained between the two components because of the similarity in expansion characteristics. T h e main current applications are in chemical process equipment and sanitary ware. ( 7 1 / 4 / 57) RP heads for mass production
Wood, A. S. Modern Plastics Inter-
national, Vol 1, No 2, pp 38-4° (February 1971) T w o major factors have led to an anticipated surge of reinforced plastics into mass production. T h e first is a result of advances in resin technology and improvement in reinforcement materials and the second is .the advance in processing of Re ingredients. Thi~ state of affairs has already led to a breakthrough into the market for automobile components and production of Re components in the 200 000 to 400 000 range is a reality. Forecasts predict a 1976 consumptioh level of 2'7 billion pounds in the US alone. (71/4/58)
T h e dynamic shear modulus and mechanical damping capacity of rubber modified rigid polymers are correlated with the concentration of rubber present and the impact strength of the composites. It is suggested that the damping peak does not have the wide significance it has hitherto been thought to have since its size, shape and position on the temperature axis are affected by composition, morphology and the method of polymer preparation. (71/4/60) Some opportunities for development in therm.plastie paper and paper replacements
Benjamin, C. and Vinty, M. J. Plastics and Polymers, Vol 39, No 13~, pp 64-76 (l~ebruary 1971) T h e cost trends of paper and plastics make the use of the latter material in packaging and communications very favourable. Cellulose fibres and plastics may be combined to give properties unobtainable by the use of either material alone. Technologies by which this can be achieved are outlined and a considerable amount of data on properties, applications and consumption is given. (71/4/61) Strength and fracture toughness of carbon fibre polyester composites
Harris, B., Beaumont, P. W.. R. and Moncunill de Ferran, E. Journal o[
Materials Science, Vol 6, No 3, pp 938-951 (March 1971)
A study of fracture behaviour of carbon-fibre/polyester composites dur. ing mechanical testing has been carried out on the scanning electron microscope. Several surface treatments were carried out on the fibres to obtain a range of composite interlaminar shear strengths and an attempt was made to correlate this parameter with composite work of fracture using a charpy impact test, a drop-weight test and a slow-bend test. T h e effect of moisture on toughness was also studied. It is concluded that improving fibre-resin bonding tends to increase brittleness and that contributions to work of fracture from the matrix and pulling fibres from the matrix against friction are in the ratio 1:4. (71/4/62)
The strength and stiffness of polymers
Frank, F. C. Proceedings o] the Royal
Society (Series A), Vol 319, p 127 (1970) It is contended that polymers may be thought of as intrinsically composite materials even though they are chemically homogeneous since fully aligned long chain polymers would have a Young's modulus in the alignment direction similar to that of steel. It is envisaged that more steps will be made to control the volume fraction of aligned chains in order to achieve desired combinations of strength and toughness even though fabrication costs are likely to be greater. ( 7 1 / 4 / 63)
Stress/strain behaviour of SAN/glass bead composites above the glass transition temperature
Narkis, M. and Nicolais, L. Journal
o[ Applied Polymer Science, Vol 15, No 2, p 469 (Febraary 1971) Stress/strain and stress/relaxation behaviour of saN/glass-bead composites above the glass transition temperature were studied and it was found that relaxation data for the filled polymer, which is independent of strain, may be calculated by the multiplication of the relaxation modulus ( l + e p ) where ep is the matrix strain, By plotting tensile stress against ep, stress/strain curves at constant strain rate for different concentrations of filler may be moved to forin a general curve, which is independent of filler content. (71/4/64)
Tensile fracture of graphite reinforced epoxy composites
fibre
Berg, C. A., Rinskv, A. Fibre Science and Technology, Vol 3, No 4, p 295 (April 1971) T h e use of high speed photography has revealed that the shattering of carbon-fibre/resin composites in tension is due to internal wave reflection after the transverse crack has passed across the specimen, and not ta dynamic crack branching. T h e longitudinal cracks which cause shattering are shown to initiate inside the specimen at points well removed from the path of the main tensile crack which runs normal to the fibre axis. (71/4/65)
Viscoelastic characterization of a nonlinear fibre-reinforced plastic
Lou, Y. C. and Schapery, R. A. Journal
of Composite Materials, Vol 5, pp 208234 (April 1971) T h e non-linear, viscoelastic behaviour of unidirectional, glass-fibre/epoxy composite material has been characterized by using isothermal, uniaxial creep and recovery tests togethe~ with a constitutive equation based on thexmodynamic theory. Specimens show an appreciable amount of nonlinearity except under loading parallel
COMPOSITES September 1971
]95