Plastics: Thermoplastic Material

QUESTION 1)A

THERMOPLASTICS

Thermoplastic material is a material made up of plastic which can be melted and molded by heating. It is also called as thermoplastic polymer. When the plastic is heated it becomes moldable and soft. The material hardens when it is cooled. Thermoplastics can be recasted into many different sn=hapes and sizes. Plastic is the example of thermoplastics

THERMOSETTINGS PLASTICS

Thermosetting is a plastic material, it cannot be repeatedly molded and melted again and again. It is also called as thermosetting polymer. It is a long chained molecules these chains are crosslinked to each and other. The long chain are held together by molecular forces known as vanderwall forces. When this material is heated the chain slips

Its decomposition gives natural by products such as gases carbondioxide and nitrogen, biomass, water and also inorganic salts. These polymers can be both naturally and synthetically prepared, and largely consist of amide, ester, and ether as functional groups. The properties and the mechanism of breakdown is determined by its structure. These polymers are synthesized by ring opening polymerization, condensation reactions and also from metal catalysts. The are examples of biodegradable polymers are as follows:

1) Poly-Hydroxybutyrate-co-b-Hydroxy valerate (PHBV) :

This copolymer consist of 3-hydroxy butanoic acid and of 3-hydroxy pentanoic acid. The units of monomers are joined by ester linkages in PHVB. Its properties vary according to ratio of both acids. 3-Hydroxy butanoic acid gives stiffness while 3-Hydroxypentanoic acid provides flexibility to it.

2) Polylactic acid (PLA) : Polylactic acid abrreviated as (PLA) is obtained by microbiological sythesis of the lactic acid which is followed by polycondensation and after that water is removed by evaporation. it can also be obtained by polymerisation of cyclic dimer of the lactic

2)They are good approximation and indicator of the contents of packaged goods and

3) It also serve as a very cheap and easy verification of nutritional panels of the product.

QUESTION 3) A

Biodiesel is a clean-burning and renewable diesel replacement which improves fuel security and provides a cleaner air to breathe i.e it does not cause pollution.It is commonly made from vegetable oils such as ,animal fats,canola oil, animal fats or recycled greases such as used cooking oil. Other feedstocks which are being developed includes pomgania trees, algae, camelina,jatropha and dry land juncea.The feedstock which contains the fatty acid is combined with alcohol . This causes the condensation of molecules of water, leaving behind rich and pure fatty acids.

HOW IS BIODESEL MANUFACTURED A chemical process called transesterificaton is used to make biodesel. This process creates two products — glycerin which is a valuable byproduct usually used in soaps and methyl esters .There are three procedure for ester production from oils and fats-

1) Direct acid catalysed esterification using