Continuous compression moulding

Other types of compression moulding and stamp forming used for continuous fibre reinforced composites are illustrated in Fig. 4.73. 

A detailed analysis of the Raman spectrum of syndiotactic PS in the region 600-850/cm was undertaken. As syndiotactic PS exhibits considerable polymorphism, spectra of various preparations including melt-crystallised syndiotactic PS, solvent-crystallised syndiotactic PS and quenched glassy materials, were studied. Peaks are assigned to conformational changes and sequences. Comparison with atactic PS is made. Study of the cross section of a compression moulded plaque exhibiting a skin/core structure revealed the continuous way the structure varied with changing crystallinity. The various physical forms of syndiotactic... 

Compounds are short (/w 0.3 mm) or long (> 0.6 mm) fibre reinforced thermoplastic or thermoset polymeric materials, which are processed automatically (injection or compression moulding), have good (mechanical) properties (for automotive, electric and electronic applications) and are relatively cheap. Composites contain continuous fibres (rovings, fabrics or mats), usually combined with thermosets, have excellent mechanical (structural) properties, but are very expensive because lack of an industrial process (mainly used in aerospace and aircraft industry). 

The manufacturing of polymer foams can take place by many techniques [11, 27, 28], such as continuous production of slabstock foams, compression moulding, injection... 

Comparison with aPS is made. Study of the cross section of a compressed moulded plaque exhibiting a skin/core structure revealed the continuous way the structure varied with changing crystallinity. The various physical forms of sPS and the routes for interchange amongst them are shown diagrammatically. 

Whilst only the author s private point of view, and one probably not shared by all others, it is expected that thermoplastic materials will gradually ease thermosetting materials, and consequently compression moulding, from their own specialised branches over the next decade. Requirements thereafter will be reduced, but certainly continue to exist and enough to supply the manufacturing capacity of most thermoset moulders for the foreseeable future. 

Microwave units are available for both continuous vulcanisation systems, for preheating of moulding blanks for compression and transfer moulding, and for heating large bales of frozen rubber prior to mixing. 

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