Thermoplastics Masterbatches / Compounds

 

Requirement of properties are different for different application. The applications are numerous but the number of plastics is limited. Moreover, many applications today require a unique combination of properties and demand very high performance. The existing plastics alone often cannot meet this high performance. One approach to high performance would be to develop new polymeric molecules. But it is not economical to develop a new plastic for every application because development  of a new plastic requires a lot of time and money.

A more rational, economical and practical approach is to modify / reinforce the existing plastic to achieve specific high performance properties. The methods for creating a plastic with balanced properties at acceptable costs are -

  • Polymer Blending and alloying of existing plastics.

  • Addition of Lubricants, Plasticizers, Stabilizers, Fillers, Reinforcing and Modifying Agents etc.

The technique of compounding polymers with other polymers, chemical additives, inorganic fillers and reinforcing fibers has given an effective tool to tailor - make materials for achieving specific balance combinations of Physical Properties, processing characteristics and cost. It is this flexibility of property manipulation that is mainly responsible for the diversity of applications of polymetric materials. Hence recently the major thrust of the material development efforts has been in the area of thermoplastic compounding with additives. Some of the key areas of modified / reinforced thermoplastic compoundings are:

A. Chemical Additives

U.V. Stabilizers, Heat Stabilizers, Antioxidants, Flame Retardants, Antistatics, Slip agents, Antislip Agents, Antifogging Agents, Antiblocking Agents, Foaming Agents, Processing Aids etc. Apart from this, many other Chemical additives are used like cling agents, metal de-activators, optical brightners, plasticizers, coupling agents, cross-linking agents, impact modifiers, lubricants, emulsifiers and so on.

B. Mineral Fillers / Extenders

The traditional use of fillers and extenders has been for reducing the amount of expensive resins needed to make a functional part. Now it is also used for physical property modification and improvement.
Almost all fillers and extenders have a variety of effects on thermoplastic resins like:

  • Increase flexural modulus

  • Reduce tensile strength

  • Increase dimensional stability and reduce creep

  • Improve thermal conductivity

  • Increase heat deflection temperature

  • Increase melt viscosity

  • Improve electrical properties

  • Improve processing

  • Extend resin

A large selection fillers and extenders is available.

Most Commonly used are

  • Talc
  • Mica
  • Antimony Oxide
  • Kaolinite
  • Aluminium Trihydrate
  • Carbon Black
  • Metal Powders
  • Feldspar
  • Starch
  • Ferrite Powder
  • Silica
  • Calcium Meta-Silicate
  • Wood Flour
  • Solid or Hollow glass spheres

Selection of Fillers

The primary objective for the usage of fillers is cost reduction and property improvement is considered as a bonus. Once the economical aspects are clear, the final choice of the filler could have been made on the basis of certain effects in the plastic composition.

C. Reinforcing Fibres

Like mineral fillers, Fibres are also used for improvement and reinforcement of physical properties of thermoplastics. Most commonly used are:

a) Aramid e) Wallostonite
b) Carbon f) Hybrids of the above fibres
c) Glass g) Carbon graphite filament
d) Asbestos h) Boron filament

Glass fibre is the only reinforcement agent readily available in India.

Note:  This is not a technical literature but only a short resume on "Additives available for compounding with Thermoplastics". Technical literature on specific product range will be made available on request.

 

Copyright 2006 Riviera Polymers Pvt. Ltd., Ahmedabad
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