Injection moulding reinforced thermoplastics

P(5) Injection moulded reinforced thermoplastic joints shall only be used in lightly loaded non-structural connections. 

Injection moulded reinforced thermoplastic joints should only be used in lightly loaded non-structural connections because they typically give a weak adhesion to almost all materials. Therefore, the load transfer from the joint component to the injection moulded reinforced thermoplastic joint member should be based on mechanical interlocking and not on the adhesion. 

Processing of LFRT or LFT - long fibre (reinforced) thermoplastics injection, composite insert moulding, compression moulding, extrusion-compression. 

A thermoplastic grille-opening reinforcement (GOR) for Ford SUVs is injection moulded from 40% mineral/glass-filled PET that can withstand on-line e-coating (210°C). HDT B (0.46 MPa) is 241°C and HDT A (1.8 MPa) is 212°C. PET GOR allows at least a 10% weight reduction and 15% cost reduction per part. 

The co-injection moulding of PVC-U with other thermoplastics (glass fibre reinforced PVC, polypropylene, ABS and polycarbonate), was investigated using the mono-sandwich process and the properties determined. Polypropylene was the only polymer not to exhibit good adhesion. The mechanical properties of the other samples were intermediate between those of the constituent polymers (104). 

Advanced Composites, D.K. Thomas, RAE, Famborough. Liquid Crystal Polymers, M.K. Cox, ICI, Wilton. CAD/CAM in the Polymer Industry, N.W. Sandland and MJ. Sebborn, Cambridge Applied Technology. Engineering Thermoplastics, I.T. Barrie, Consultant. Reinforced Reaction Injection Moulding,... 

Report 8 Engineering Thermoplastics, I.T. Barrie, Consultant. Report 10 Reinforced Reaction Injection Moulding,... 

Extrusion and injection-moulding are the economically most attractive processing methods of thermoplastic-based composites. The extrusion press processing (express-processing) has been developed for the production of flax fibre reinforced PP at the research centre of Daimler Benz [7]. In this process, flax fibre non-wovens and PP melt films are alternatively deposited and moulded. A production process for PP semi-products reinforced with lignocellulosic fibres in the form of mats has been developed by BASF AG [7]. Fibre mats are produced by stitching together layers of fibres which have previously been crushed. 

A typical helmet is expected to be between 5 and 10 mm thick, dependent on both material type and applicatioa The shell thickness is normally determined experimentally by the penetration test. The shell canbe made of either an injection-moulded thermoplastic or a pressure-moulded resin system, reinforced with ballistic resistance fabrics/fibres (Mills, 1996). Energy is absorbed when the helmet is impacted, with the shell bending and deformation of the underlying foam. The amount of the impact energy absorbed by the foam depends on ... 

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). 

Ganster J, Pinnow M, Fink H-P (2006) High tenacity man-made cellulose fibre reinforced thermoplastics - injection moulding compounds with polypropylene and alternative matrices. Compos A 37 1796-1804... 

Hot-curing materials with randomly arranged reinforcement are available in grades suitable for processing by conventional compression, transfer or injection moulding. Short fibre-reinforced thermoplastics are usually injection moulded. Processes that are peculiar... 

Vincent and co-workers [151] studied the influence of flow on the fibre orientation and mechanical properties in the injection moulding and extrusion of fibre reinforced thermoplastics. 

Short fibre reinforced thermoplastic composites can be processed by most of the classical thermoplastic processing techniques, such as, extrusion and injection moulding. A detailed discussion is provided for these classical thermoplastic processing techniques in Section 9.1. 

The most important technique to consider for reinforced thermoplastic composites is injection moulding. Since the melt viscosity is higher whenever fibres are included in the system, the injection pressures necessary are higher than their unreinforced thermoplastic counterparts. In addition, the product is much stiffen Although the cycle times are less for reinforced thermoplastics, increased stiffnesses can certainly effect the ejection, hence the mould design needs to be modified considerably. 

The method by which the compound will be moulded or shaped naturally dictates the form of reinforcement. In thermoplastic compounds (which will be predominantly injection moulded), short-length fibre or particulate reinforcement is used, but there has been important development of so-called long -fibre compounds, with a higher ratio of reinforcement to resin matrix and a longer... 

Parallel to thermosetting SMCs and BMCs are thermoplastic moulding compounds in sheet form, known as glass mat thermoplastics (GMTs), and compounded into standard granules for injection moulding and extrusion. Most thermoplastics are theoretically capable of such combination with reinforcement, but the main types used commercially at present are polyamide (PA) and polypropylene (PP). 

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