PLASTICS ADDITIVES SUMMARY

Many applications for polymers require properties additional to those provided by the base polymer.  The additives available are many and varied and in some instances, where demand is sufficiently high, may be added to a particular grade of polymer at the production stage.

Please Note: This page is for information purposes only. Rutland Plastics is an Injection Moulder and does not supply plastics additives.

The following list of additive types is by no means exhaustive but covers the most commonly used.  In time links will be added to each of these taking you to a page with more information on the relevant additive.

COLOUR PIGMENTS

Small particles of high density colour that can be added to a natural polymer to produce the desired colour.  Special effects, such as metallic sparkle, pearlescent, etc are also available.

ANTIMICROBIALS/ANTIBACTERIALS

Used in plastic products to kill bacteria.  Many NHS hospitals now have plastic items containing this additive to help in their battle against infections such as MRSA.

BIOSTABILISERS

Help prevent the deterioration of plastic material where it may be susceptible to biological attack.

ANTIOXIDANTS

Help prevent oxidation – the reaction of the polymer with oxygen.  Oxidation can result in loss of impact strength, surface cracks and discolouration.

ANTISTATICS

Help prevent the build up of static electric charge.  Plastics have a tendency to build up static charge on the surface which can disturb processing and can be an issue for hygiene and aesthetics.

BIODEGRADERS

Make plastics softer and more flexible and enhance the degradability of the product.

FOAMING/BLOWING AGENTS

These form a foam like internal structure to the moulding.  Useful in reducing sinkage and weight in thick section parts, for instance.

LUBRICANTS

External to prevent damage to the mould or part during processing.  Internal slip agents to make the surface more slippery if required as a feature of the product.

FILLERS

These can include chalk, talc and glass fibres or spheres.  Generally added to improve strength or stiffness.

FLAME RETARDANTS

To prevent ignition or spread of flame in the plastic material.  These are usually added at the initial manufacturing stage with many grades of flame retardant polymers widely available.

FRAGRANCES

Primarily for products in the home, such as nappy bags.

IMPACT MODIFIERS

Improve a plastic material’s ability to absorb shocks and resist impact without cracking.  Particularly useful for PVC, polystyrene and polypropylene.

UV STABILISERS

Many polymers degrade over time when exposed to UV light.  UV stabilisers can be added to lengthen the life of a product under these circumstances.