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The CORRECT CHOICE is (b) Acid SOLUTION catalyst

Easy explanation: General resin characteristics can be controlled by adding an acid solution catalyst with excess phenol which produces LINEAR SOLUBLE thermoplastics.

Correct ANSWER is (a) Alkali conversion-Solubilization-Acid regeneration

Explanation: Initially the cellulose reacts with NaOH to FORM alkali cellulose which UNDERGOES solubilization by CS2 and then gets converted to cellulose by the ADDITION of acid.

Right choice is (a) Xanthate process

To explain I would say: Cellulose is PRODUCED by viscose or xanthate process, with the CUPRAMMONIUM produced CONTRIBUTING only minor PRODUCTION.

Right ANSWER is (C) Wood pulp

For EXPLANATION: The main raw MATERIAL for the manufacture of VISCOSE rayon includes wood pulp, other strengthening additives. Its production produces toxic effluents.

Correct OPTION is (c) LINEAR molecules formed by extrusion

For explanation: SYNTHETIC polymeric fibres are linear molecules formed by extrusion or spinning into small diameter. NETWORK polymers are multifunctional MONOMERS forming three or more active covalent bonds.

The correct choice is (C) Wool

Easiest EXPLANATION: Wool sector of the textile industry is BETTER KNOWN as WORSTED industry, as its main product is suiting-all wool (AW), polyester wool (PW) and polyester viscose.

The correct answer is (a) Phenolics

To elaborate: Phenolics are low cost polymers with excellent physical and ELECTRICAL PROPERTIES and fast curing characteristics. Pigments are added to ENHANCE its COLOUR.

The CORRECT choice is (b) LOW pressure Ziegler process

To EXPLAIN I would say: High purity polyethylene is manufactured by desulphuring and removing the light ends FOLLOWED buy removal of EXCESS oxygen combined with titanium tetrachloride to produce a saturated paraffin.

Correct choice is (d) Viscose

To EXPLAIN I WOULD say: Viscose RAYON is more COMMONLY known as poor MANS silk due to its vast material application and is cost effective.

The correct option is (a) Polyacrylonitrile

To elaborate: ACRYLICS constitute one of the four major classes of synthetic FIBRES. Polyacrylonitrile is the major component of acrylic fibres. A comonomer is generally incorporated to IMPROVE such fibre properties.

The correct CHOICE is (B) Nylon

To EXPLAIN I would say: Nylon is most commonly USED dying fibre because of its excellent dying properties and its COST effective.

The CORRECT choice is (a) True

For explanation I would say: Epoxy POLYMERS are manufactured largely by BATCH PROCESSING because of low tonnage,

Multiple formulation marketing.

Right choice is (a) True

For explanation I WOULD say: Epoxy reins exhibit EXTREME VOLATILITY because of POSSIBLE combinations of properties such as CHEMICAL stability, reactivity, excellent adhesion, good abrasion and electrical properties.

Correct ANSWER is (a) By adding water

The explanation: The residual catalyst is REMOVED from the POLYETHYLENE by adding water. Water is ADDED because the residual catalyst is highly flammable in dry conditions. Adding acid would INCREASE the flammability.

Correct choice is (a) Polyol

The EXPLANATION is: Polyols are used as main raw material in the MANUFACTURE of POLYURETHANE foams along with methyl di-phenyl diisocyanate and TOLUENE diisocyanate.

Right OPTION is (c) adipic acid

To explain I would say: 6,6 NYLON is MANUFACTURED from adipic acid. This adipic acid then reacts with hexamethylene DIAMINE to form polyhexamethylene adipamide or 6,6 nylon.

Correct choice is (c) ADDITION of oxygen atom ACROSS a C=C

Easiest explanation: Epoxidation is the addition of oxygen across a C=C to give

The oxygen transfer agent can be PERACIDS such as peracetic acid, hydrogen peroxide, or chlorohydrin FOLLOWED by HCl removal.

Right choice is (C) 80-140 °C

Explanation: PVC has a softening point ranging from 80 °C-140 °C INCREASING with the degree of after chlorination. After 140°C it decomposes LIBERATING HCL.

The CORRECT choice is (C) EMULSION polymerization

Easy explanation: Emulsion polymerization technique is DONE in order to produce high purity polymer. In Emulsion polymerization, a typical formulation is 100 parts of water, 100 parts of vinyl monomer, 1 part of persulfate catalyst and 1.5 parts of detergent emulsifier.

The correct option is (a) Spinning

For explanation: Synthetics are PREPARED from molten linear polymers or a SOLUTION of polymers by extrusion through a DIE containing 20 to 15000 small holes, SOLIDIFYING and collecting a group of threads as a filament.

Correct choice is (a) Resorcinol

The best I can explain: EPICHLOROHYDRIN’s are CONDENSED with other HYDROXYL groups in COMPOUNDS such as resorcinol, HYDROQUINONE, ethylene glycol and glycerol.

The correct answer is (a) Polymers made from monomers having bifunctional GROUP

For explanation I WOULD SAY: Polymers made from monomers having the bifunctional group are ethenic because ethylene has the simplest all hydrogen atom structure and others are substitutions of other groups at W, x, y and z positions.

The CORRECT choice is (c) Heating-Carbonization-GRAPHITIZATION

For explanation: The PAN fibres are first preheated to 300°C and the undergoes carbonization at 1600°C TILL a high strength carbon fibre is formed. Finally, it undergoes graphitization at TEMPERATURE up to 3000°C.

Right answer is (b) False

For explanation: The CARCINOGENIC properties of fine asbestos FIBRES have decreased its USE. It causes SERIOUS health hazards. So, it is not USED in reinforcing fibre.

Correct ANSWER is (d) Polypropylene

The best I can explain: Acrylonitrile, butadiene and styrene copolymer are examples of ABS resins. They are CLASSIFIED as engineering PLASTIC USED in automobile components, refrigerator PARTS etc.

The correct option is (a) True

The best explanation: Composite MATERIALS are reinforced PLASTICS in which a strong ceramic or other fibre is positioned in a PLASTIC MATRIX. The ORIGINAL material in this category was glass fibre reinforced resins.