Results 261 to 270 of about 34,388 (294)

Bonding in polypropylene fibre reinforced concretes

Cement and Concrete Composites, 1989
Abstract The geometry of fibrillated polypropylene fibres after mixing in concrete, and the nature of the fibre interface in the hardened concrete, were characterised by optical and scanning electron microscopy, to resolve the bonding mechanisms in this system.
A. Bentur, S. Mindess, G. Vondran
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Morphological investigations of polypropylene single-fibre reinforced polypropylene model composites

Polymer, 2001
Melt-spun isotactic polypropylene (iPP) fibres have been prepared with moduli of about 12 GPa and strength of 730 MPa. Single-fibre model composites are prepared by embedding constrained high-modulus iPP fibres in thin films of a matrix material based on the same isotactic polypropylene grade. The morphology of these composites has been investigated by
Loos, J., Schimanski, T., Hofman, J., Peijs, A.A.J.M., Lemstra, P.J.   +4 more
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Transcrystallization of polypropylene on carbon fibres

Polymer, 1997
Measurements have been made using a polarized optical microscope equipped with hot stages to investigate the transcrystallization of polypropylene on carbon fibres. Both the nucleation rate and induction time at various crystallization temperatures were measured. It has been found that the induction time is inversely proportional to the nucleation rate.
Chi Wang, C.R Liu
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Bonding of air-formed wood fibre/polypropylene fibre composites

International Journal of Adhesion and Adhesives, 1991
Abstract The effectiveness of a maleated polypropylene (MAPP) as a coupling agent in wood fibre/polypropylene fibre composites made by non-woven web technology has been evaluated. The composite panels were made with 70 or 85% wood fibre, wiht the MAPP being incorporated in the panels at a level of 1 or 3% by spraying an emulsified form on the wood ...
A.M. Krzysik, J.A. Youngquist
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Crystallization of carbon fibre reinforced polypropylene

Journal of Materials Science, 1990
Polypropylene (PP) was compounded with carbon fibre of various contents (0, 5, 10, 15, 20 vol%) using a single and a twin screw extruder. The influence of both the carbon fibre content and the compounding method on the thermal behaviour and characteristics of crystallization was studied using differential scanning calorimetry (DSC), polarizing optical ...
Jo�o K. Tan, Takeshi Kitano, Tatsuko Hatakeyama   +2 more
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Nuclear magnetic relaxation in polypropylene fibres

Acta Polymerica, 1988
AbstractThree types of drawn PP fibres have been investigated by nuclear magnetic relaxation methods. The two minima observed in both the temperature dependence of T1 and T2eff are related to the well known β‐and α‐processes, respectively. The results of the experiments show that in particular the crystalline regions are influenced by drawing.
J. Murin, D. Geschke, P. Holstein, D. Olcak, L. Sevcovic, L. Mucha   +5 more
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Magnetic study of elongated polypropylene fibres

Czechoslovak Journal of Physics, 1966
A study is made of the magnetic properties of polypropylene fibres (PP) subjected to permanent unidirectional deformation at room and higher temperatures of the medium (120°C). It follows from the results that the values of the magnetic susceptibility, measured perpendicular to the axis of the fibres, change as a function of the relative elongation ...
M. Rákoš, R. Šimo, Z. Varga
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Toughness of polypropylene fibre-reinforced concrete

Composites, 1985
Abstract The toughness index of polypropylene fibre-reinforced concrete has been determined from three test-specimen geometries — compact tension, compact compression and beam bending tests. The toughness index used in this study is a modification of the ACl toughness index: a fracture test is continued until the deflection is twice that which occurs
B. Barr, P.D. Newman
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Fracture toughness of polypropylene fibre concrete

International Journal of Cement Composites and Lightweight Concrete, 1981
Abstract The paper describes two simple tests which have been developed to determine the fracture toughness of concrete materials. In the first case, the test is carried out using ordinary concrete cubes, modified by the introduction of two slits, and then subjected to an eccentric load. In the second case, CTS specimens are used to evaluate fracture
B.I.G. Barr, W.T. Evans, R.C. Dowers
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Structural studies of isotactic polypropylene fibres

1997
The present work shows that sh-uctural characteristics of isotactic polypropylene fibres in terms of molecular orientation and crystallinity can be obtained with the use of X-ray diffraction, thermal analysis and infrared spectmscopy. Polarised infra-red spectra of the samples have been anelysed in detail and used for the characterisation of the ...
KARACAN, İsmail, Wang, I. Chun
openaire   +2 more sources