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MATHS TALENT TEST SCORES RELEASED OVERALLS

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POLYMERS AND PLASTICS

  • The polymer is a substance formed by the combination of two or more monomers.
  • the polymer is a greek word, poly means many, mers means parts.
  • the monomer is a simple molecule.

polymers are two types they are natural and artificial.


  • natural polymers are obtained from nature directly.
example:natural rubber,cellulose,protein,silk etc,.

  • artificial or synthetic polymer, these are formed by the combination of organic compounds.
example:nylon,bakelite,poly vinyl chloride etc,.

the process of synthesizing the polymer is nothing but polymerization.polymerization is three types:-

ADDITIONAL POLYMERISATION:


a polymer is formed by the combination of two or more monomers, without losing of by-products
example: POLYTHENE, POLYSTYRENE, POLYVINYL CHLORIDE.

CONDENSATION POLYMERISATION:


a polymer is formed by the combination of two or more monomers, with losing of by-products.
example: BAKELITE, UREA FORMALDEHYDE RESIN.

CO-POLYMERISATION:


a polymer is formed with a combination of two completely different monomers and form a new product.
example: BUNA-S RUBBER OR STYRENE RUBBER.

NATURAL RUBBER: 

it is an isoprene polymer.
example: latex from the trees.

ELASTOMER:

it is a synthetic rubber, which can be stretched up to twice its length.
example: BUNA-S OR STYRENE, NEOPRENE.

VULCANIZATION is the process of adding sulfur at 110-150 degrees Celcius to improve the quality of rubber.

PLASTICS:


  • plastics are the high molecular weight polymers formed by the applications of heat and pressure.plastics are two types:
  • thermoplastics nothing but their molecules are a linear chain.
  • thermosetting plastics nothing but their molecules have the cross-linked chain.
DIFFERENCE BETWEEN THERMOSETTING AND THERMOPLASTIC;



ALL THE EXAMPLE STRUCTURES:

the structure of isoprene or natural rubber :

the structure of  polythene:

the structure of pvc :

the structure of polystyrene:


the structure of bakelite:

the structure of urea formaldehyde:

the structure of styrene rubber or buna-s:

the structure of Teflon :

the structure of vulcanized rubber:

the processing structure of latex:

note:

  • the urea was invented by the scientist wholer. the for this compound is CH₄N₂O.

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NEWTON LAWS

ONE NEWTON = ONE KG METER PER SECOND SQUARE.  NEWTON FIRST LAW : states that inertia of motion. any object can't be move unless there is a force exerts on it. NEWTON SECOND LAW: states that force is equal to the product of mass into acceleration(momentum). NEWTON THIRD LAW: states that when two objects interact together then they apply forces to each other equal size and opposite direction. which means for every action there is an equal and opposite reaction.
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ALKANES AND ALKENES,ALKYNES

ALKANES: these are also called paraffin. alkanes are saturated hydrocarbons. the formula of alkanes (CnH2n+2). when the H atom is removed from the alkane then it is replaced by the name of alkyl. the formula for alkyl is (Cn H2n+1). the carbon atom in it shows the sp3 hybridization. the bond length is equal to 1.54°A. ALKENES: these are also called as olefins means form oil products. it possess a double bond between them. the formula is (CnH2n). the carbon atom in it shows the sp2 hybridization. the bond length is equal to 1.34°A. ALKYNES: these are also called as acetylenes. the formula for this is (Cn H2n-2). the carbon atom in it possesses a triple bond and also shows the linear shape means it is in an sp hybridization. the bond length is equal to 1.20°A.
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