Dielectric material: plastics, Physics

Plastics are polymers, meaning they are made up of molecules from many different elements. By utilizing different combinations, new polymers are made that can be manipulated from many different things. Plastics are organic materials of higher molecular weight and are capable of being formed into a desired shape during or after their manufacture. However, organic materials may to be the sole constituents of plastics. The term plastic is used very frequently in common terminology even for materials which are not really plastics if viewed from the definition given above. Resin is the substitute world normally used in insulation technology in place of plastic. Plastics are synthetic resins obtained basically in two different ways, by linear polymerization and by poly condensation. The recurring chemical reaction by which molecules weight composition is called "POLYMERIZATION", and the linear polymerization is a reaction is chemical in which high molecular compound is obtained from a lower molecular compound. Without evolution of a by product in linear polymerization several monomers are linked to one another and form a single polymer molecule. These molecules are relatively easy to recycle. The polymers achieved through linear polymerization are known as "Thermoplastics". Thermoplastics can be melted and reformed any number of times. Thus they are relatively easy to recycle. When the reacting molecules combine in such a way that there is evolution of a by product of the molecular weight, like water, the process is called 'Condensation Polymerization "and this irreversible chemical reaction between different low molecular compounds. There are two general types of the linear and the spatial condensation. Thermosetting plastics are melting on heating but are converted into a rigid solid mass if maintained at an elevated temperature long enough. They become unable to maintained melt after this and hence become insoluble in any solvent.

Spatial polymers are characterized by:

  1.    Insolubility and poor insulating properties
  2.    Hardness and brittleness
  3.    Not capable of fibre formation
  4.    Good mechanical properties
  5.    High Hygroscopicity

Linear polymers are characterized by:

  1.    Good solubility and good insulating properties
  2.    Flexibility and elasticity
  3.    Capability of fibre formation
  4.    Poor mechanical properties
  5.    Low Moisture content

Posted Date: 7/7/2012 6:05:15 AM | Location : United States







Related Discussions:- Dielectric material: plastics, Assignment Help, Ask Question on Dielectric material: plastics, Get Answer, Expert's Help, Dielectric material: plastics Discussions

Write discussion on Dielectric material: plastics
Your posts are moderated
Related Questions
A simple pendulum Tie a cord at least 2 m long to some object like a stone or a small metal ball. Suspend this in a doorway or from a hook in the ceiling and begin it swinging

Interfacial polarization takes place whenever there is an storage of charge at an interface between two materials or between two regions in a material. As shown in the material ha


The Schottky diodes are a semiconductor diode with a low forward voltage drop and a very fast switching action. The voltage drop at forward biases of around 1ma is in the range 0.1

Phase advancers: Phase advancers are used to better the power factor of induction motors. The low power factor of an induction motor is because of the fact that its stator winding


A boat is traveling along a circular path having a radius of 20 m. Determine the magnitude of the boats acceleration if at a given instant the boats speed is v = 5 m/s and the rate

Light is quantized. Photons are light quanta. It has zero REST mass. Therefore, it always travels at maximum speed permitted by relativity

An x-ray photon collides with a free electron, and the photon is scattered. During this collision there is conservation of: a) Momentum but not energy b) Neither momentu

Fifth Harmonic-Standing Waves on a String There are a variety of patterns that could be generates through vibrations inside a string, slinky, or rope. Every pattern corresponds