Polyvinyl chloride (PVC) is a versatile and resource efficient thermoplastic with the widest variety of applications of any of the plastics family making it useful in practically all regions of human activity.
Without additives pvc pellet would stop being a really useful substance, nonetheless its compatibility with a variety of additives – to soften it, colour it, make it more processable or longer lasting, results in a wide range of potential applications from car underbody seals and flexible roof membranes to pipes and window profiles. PVC products could be rigid or flexible, opaque or transparent, coloured and insulating or conducting. There is not just one PVC but a whole group of products tailor-designed to suit the requirements of each application. Unlike the majority of thermoplastics, the majority of PVC applications have a lifetime which is between 10 and a century. This involves proven durability and stabilisers play a significant part in achieving such performance. All polymers require stabilisers of merely one sort or any other; PVC is no different in this respect.
Before PVC can be created into products, it has to be combined with a range of special additives. The primary additives for all those PVC materials are stabilisers and lubricants; in the matter of upvc compound, plasticisers can also be incorporated. Other additives which might be used include fillers, processing aids, impact modifiers and pigments. Additives pvcppellet influence or determine the mechanical properties, light and thermal stability, colour, clarity and electrical properties of the product. As soon as the additives are already selected, these are together with the polymer inside a process called compounding. One strategy uses an intensive high-speed mixer that intimately blends all the ingredients. The end result is a powder, known as the ‘dry blend’, which can be then fed into the processing equipment.
The 2nd strategy is to blend the constituents in either the lowest or high-speed mixer and after that transfer the powder to your melt compounder. This can either be a compounding extruder, or other special equipment for making pvc compound. These create a melt which, when cool, is cut into granules ready for processing. In a specialised process, liquid compounds called plastisols, are made as dispersions of very fine PVC polymer particles in liquid organic media. PVC compounds are made into products using a variety of processing methods which include extrusion, injection moulding, blow moulding, calendering, spreading and coating.