Additives in plastics

Additives in plastics
Additives are added for many reasons some of the additives and its purpose we are going to discuss here. Additives are also called as Agents
Before that we get know about the term Polymers why because in this blog the term polymers only used so it’s essential to know what is polymers

Polymers:
Synthetic Large molecules are made by joining together thousands of small molecular units know as monomers. The process of joining the molecules is called polymerization and the number of units in the long molecule is known as degree of polymerization. The name of many polymers consists of the name of the monomers with the suffix poly.
Now your clear about the term polymers, ok now again we come back to the Additives / Agents, types of agents are listed below according to the requirement the additives are used.

Antistatic Agents:
Most polymers are poor conductors of current build up a charge of static electricity. Antistatic agent attracts moisture from the air to the plastic surface, improving its surface conductivity and reducing the like hood of a spark or a discharge.

Coupling Agents:
Coupling agents are added to improving the bonding of the plastic to inorganic filler materials. Such as glass fibers. A variety of silances and titanates are used for this purpose.

Fillers:
Some filler such as short fibers or flakes of inorganic materials. Improve the mechanical properties of a plastic. Others called extenders permit a large volume of a plastic to be produced with relatively little actual resin. Calcium carbonate, silica and clay are frequently used extenders.

Flame retardants:
Most polymers are organic materials, are flammable. Additives that contain chlorine, bromine, phosphorous or metallic salts reduce the likehood that combustion will occur or spread.



Lubricants:
Lubricants such as wax or calcium stearate reduce the viscosity of the molten plastic and improve forming characteristics.

Pigments:
Pigments are used to produce colours in plastics.

Plasticizers:
Plasticizers are low molecular weight material which alters the properties and forming characteristics of the plastic. An important example is the production of flexible grades of polyvinyl chloride by the use of plasticizers.

Reinforcement:
The strength and stiffness of polymers are improved by adding fibers of glass, carbon etc.

Stabilizers:
Stabilizers prevent deterioration of the polymer due to environmental factors. Antioxidants are added to ABS, polyethylene and polystyrene. Heat stabilizers are required in processing polyvinyl chloride. Stabilizers also prevent deterioration due to ultra violet radiation.
‘Deterioration’Means Become progressively worse.


Comments

Post a Comment

Popular posts from this blog

What are the most fascinating science facts?

Image
The blood would appear  green  in color in deep sea/ocean. Water can  boil  and  freeze  at the same time. If you took out all the  empty space  in our atoms, the human race could fit in the  volume of a sugar cube . Lasers can get  trapped  in a waterfall. A  teaspoonful  of neutron star would weigh  6 billion tons . The Eiffel Tower can be  15 cm  taller during the summer. Babies have around  100 more bones  than adults. An egg looks like a  crazy jellyfish  underwater. A flea can  accelerate faster  than the Space Shuttle. A single solar flare can release the equivalent energy of  millions of 100 megaton atomic bombs . Cats always land on their  feet . If you  spin  a ball as you  drop  it ,  it  flies .
Read more

FIFA WORLD CUP HISTORY

Image
Federation International The Football Association The success of the Olympic Football Tournament intensified FlFA's wish for its own world championship. Questionnaires were sent to the affiliated associations, asking whether they agreed to the organization of a tournament and under what conditions. A special committee examined the question, with President Jules Rimet the driving force. He was aided by the untiring Secretary of the French Football Federation, Henri Delaunay. Following a remarkable proposal by the Executive Committee, the FIFA Congress in Amsterdam on 28 May 1928 decided to stage a world championship organized by FIFA. Now, the organizing country had to be chosen. Hungary, Italy, the Netherlands, Spain and Sweden submitted their candidatures. Right from the start, Uruguay was the favorite and not simply for its Olympic gold medal wins in 1924 and 1928 - the country was celebrating its 100th anniversary of independence in 1930 at great expense. Moreover, it...
Read more

CRANKCASE

http://en.wikipedia.org CRANKCASE         The main body of the engine to which the cylinder are attached and which contains the crankshaft and crankshaft bearings is called crankcase.This members also holds other parts in alignment and resists the explosion and intertia forces.It also protects the parts from dirt etc. In the crankcase only the engine oil are stored in self lubricate syst em the crankcase play an important role the scoop used for splashing to the engive wall are taking oil from the crankcase only so I play a majore role in lubrication system      Crankcase forming an engine block ,crankcase  are the basic engine structural component   crankcase often has an opening in the bottom to which an oil pan is attached a gasketed bolted joint. Material used for crankcase  Material which is used for making crankcase are engine block mostly cast aluminium crankcase are made via sand casting ...
Read more