Types of polymerisation, Mechanical Engineering

Types Of Polymerisation

When some of bifunctional molecules connect in a chain structure, the reaction is termed as addition polymerisation.  However, these polymerizations do not take place on its but has to be initiated, propagated and after that terminated. Presence of split H2O2 or 2HO usually initiates the reaction. Hydrogen peroxide is heated to split in two free radicals 2HO that initiates polymerisation.  The energy of the chain polymer is lower than that of the independent monomers such form the chain and thus the chain grows in length fast after initiation. By addition of trace impurity the reaction is terminated. The reaction termination may airse because of two ends of joining of the chain or because of supply of exhaustion of the monomers also. Ethylene or C2H4 polymerising in polyethylene and vinylchloride or C2H3Cl polymerising in polyvinyl chloride are the illustrations of addition polymers.

The improvements in polymer technology have led to the knwoing that monomers of two various types can join in a single chain in co-polymerisation.  For illustration, monomers of vinylaecetate and vinylchloride form a chain of copolymers as demonstrates in figure of Co-polymerisation of Vinylchloride or C2H3Cl and Vinylacetate or OCOCH3. Vinylacetate molecule along with dual bond between oxygen and carbon is also demonstrates in same figure. This double bond opens into two bonds to join along with another opened bond of carbon of vinylchloride.

                                                                    151_Polymerization 4.png

                                 Figure: Co-polymerisation of Vinylchloride or C2H3Cl and Vinylacetate or OCOCH3

A copolymer is greatly like a solid solution in crystalline materials because its properties are very much dissimilar than those of constituents.A third type of polymerisation reaction happens when a second non-polymerisation molecule is generated as a byproduct. This reaction is termed as condensation polymerization.  The genearl byproducts of condensation polymerisation are water, CH3OH or HCl. In a characteristic reaction of polycondensation among hexamethylenediamine and adipic acid long chain nylon molecules are produced along with water as a byproduct.

Posted Date: 2/27/2013 4:39:55 AM | Location : United States







Related Discussions:- Types of polymerisation, Assignment Help, Ask Question on Types of polymerisation, Get Answer, Expert's Help, Types of polymerisation Discussions

Write discussion on Types of polymerisation
Your posts are moderated
Related Questions
Clutch: Clutch is a part which is used to transmit the rotary motion of one shaft to another shaft, when desired; the axis of second shaft must be in line with the axis of the fir

what is interference and undercutting?

Define Flavorings in IGES Flavorings : IGES contained several ways to capture the same information, which made proper interpretation largely dependent on the particular  "fla

Dynamic Magnifier: This is function of frequency ratio. Forced Vibration: While the system is continuously excited by an external force or internally produced force, the v

Explain Roughness width and Roughness width cut off? Roughness width: - Roughness width is the distance parallel to the normal surface between successive peaks or ridges whic

Q. Minimum Design Metal Temperature? The MDMT and coincident pressure shall be selected in consideration of the operating phases. Reliable administrative procedures to control

Results for the Underlying Problem The rules mentioned above and several variants of these rules that became out to be inferior are tested for eight various conditions of the


Platforms: Platforms are places where trains stop and passengers entrain and detrain. For BG operations, the length of the platform should be about 30 m. Figure gives the

What is UPR Novel architecture for complete CAD data exchange, called the Universal Product Representation (UPR).