Moulded parts

Note The injection/compression moulding process capability maps 1, 2 and 3 are used for large parts with a major dimension greater than 50 mm typically and/or for large production volumes. Map 4 is for injection moulded parts that have a major dimension less than 150 mm and which are produced in small volumes. 

Better strength of flow fines in moulded parts... 

Flame retardants cause the plastic material to be safer in use in its final form. They are only used when the marketplace requires it in a wide range of applications spanning the construction, moulded parts, sealants, coatings and textile industries. High levels (up to 25 %) of FR are required in polypropylene - one of the most difficult plastics to render flame retardant - to meet standards for certain applications, such as in the... 

These results at 20° C refer to low stress moulded parts made from Makrolon. The chemical resistance of this material may be affected by mechanical stresses and high temperatures. The polymer High Density 3... 

One of the primary limitations of PET is related to its slow rate of crystallization from the melt. A consequence of this is that relatively long cycle times are required to provide crystallinity in PET. When this is achieved, it is often accompanied by opacity and brittleness, due to the relatively large size of crystallites formed by thermal crystallization. Crystallinity itself is often desirable in moulded parts, due to the higher thermal and mechanical stability associated with it. Crystallinity is especially desirable when parts are intended to be subjected to elevated temperatures since if the PET components are amorphous they will anneal at temperatures above 80 °C. 

Nucleating agents in PET also allow faster demoulding times, that is, the injection moulded part can be ejected from the mould more quickly or at a higher temperature. 

Injection- and blow-moulded parts, seals and gaskets resisting oils, handles of motorbikes, cable guides... 

It is imperative that the final selection is made with the assistance of a polymer specialist. 3.6 Precision of the moulded parts... 

A powdered dry-blend of plasticized PVC is introduced into a hot mould for an appropriately adjusted time to obtain a consistent wall thickness of gelled PVC. The dry-blend excess is removed and then the mould is cooled to strengthen the moulded part. 

The instrument panel (IP) on the Mazda 6 features an extrusion process that enables in-line forming for both ends of parts. The cost savings are more than 10% compared with an extruded/injection-moulded part. 

Glass fibre braids impregnated with PEEK for high-performance moulded parts. 

The big underbody panel on the new 5 Series from BMW with variable stiffness and density values within the panel produces a weight saving of 30% compared with a similar glass-reinforced PP compression-moulded or injection-moulded part. 

It has been found that moulding conditions can affect almost every property of moulded parts. Among the properties affected are impact strength, crack resistance, and... 

DuPont s Biomax is used in a number of specialty packaging applications, injection-moulded parts, coatings for paper, thermoformed cups and trays, and films because of its superior barrier properties. DuPont has targeted fast-food disposable packaging, as well as yard-waste bags, diaper backing, agricultural film, flowerpots, and bottles, for particular development. 

PEA CF2=CF2 + RfOCF=CF2 Injection-moulded parts for use in aggressive environments. 

Finally, crystalline microstructure of PET is not significantly modified by the blending if one except a small nucleating effect of the non-reactive additive that can be observed in laboratory conditions. However, this nucleating effect is not due to the nodule itself [20] as no transcrystallisation can be observed on particles. Additionally, this nucleating effect does not lead to significant evolution in mean spherulite diameter in injection moulded parts. 

The mechanical and physical properties of moulded parts, particularly those made of thermoplastics, do not depend only on the chemical constitution of the material and its properties. The processing conditions also exercise a considerable influence (Wilkinson Ryan, 1999). Properties such as strength, toughness, hardness may vary to a greater or lesser extent in the same material, or can be selectively varied by choosing a particular processing technique. Those factors that determine the quality... 

The tissue culture surface begins with a select grade of virgin polystyrene that has been chosen for high purity and minimal additive content. The moulded part is then subjected to conditions of either corona discharge or a gas plasma. 

For plasma treatment, the moulded part is placed in a vacuum chamber under low pressure in which an electrical discharge ionizes a specific gas that is present. The resulting gas plasma generates a reaction with the polystyrene substrate, with the result that randomized chemical groups become covalently attached to the surface. 

Formulations for producing polyurethanes (PUs) by reaction injection moulding (RIM) usually contain mixtures of polyols and diols in order to achieve the desired properties in the moulded part. The present work forms part (1) of a systematic investigation into the effects of polyol blends and glass fibres on the physical properties of unfilled and filled PUs formed by RIM. In the case of unfilled PUs, by using a multi-component polyol mixture, it is possible to investigate the effects on properties of (a) polyol structure, molar mass and functionality, (b) the relative proportions of diol-based hard blocks and triol-based soft blocks and (c) polyol blend compatibility. The... 

A complete process chain for moulded parts made of PA6 is shown in Fig. 1.2. PA6 is synthesized in a polymerisation step from the monomers caprolactam and water. The production of caprolactam itself can be traced back to benzene which is isolated from crude oil or formed from crude oil in a cracking process. The polymer melt is degassed from unreacted monomers and then further processed to condition it for the manufacturing of semi-finished products and of moulded parts. The poljmier material in the moulded parts may be eventually recycled and reused in the polymerisation after a polymer degradation reaction has been carried out. 

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