Solutions.
Polymer - Correct Answers a substance composed of molecules with large molecular
mass made up of repeating structural units (chain), or monomers, connected by a
covalent chemical bond
Synthetic - Correct Answers Describing a substance that has been made artificially
through chemical synthesis, i.e. one that does not come from a natural source
Synthetic Polymers Types - Correct Answers Fibers (aramid (Nomex, Kelar, Nylon)
polyester);
Plastics (acrylics (plexiglass), PET);
Elastomers or Rubbers (SBR tires);
Protective Coating (paint, varnish) (liquid);
Adhesives (cyanoacrylates (superglue)) (liquid)
Raw material for polymers - Correct Answers crude oil or natural gas
Steps to Manufacture Polymers from Crude oil - Correct Answers Step 1: fractional
distillation to get needed HCs
Step 2: Cracking to produce monomers
Step 3: Polymerization to produce polymers
3 groups of HCs according to their structure - Correct Answers Parafines (~25%)
Naphthenes (~50%)
Aromatics (~17%) and other non-HCs
Paraffins - Correct Answers Saturated chains, single C-C bonds
Naphthenes - Correct Answers cycloparaffins,
Saturated rings, single C-C bonds
Aromatics - Correct Answers Unsaturated ring
Saturated - Correct Answers HCs with only single bonds. Cannot break bonds anymore
Unsaturated - Correct Answers have doubles bonds
Fractional Distillation - Correct Answers Separate crude oil into various hydrocarbon
fractions. Effective separation can be achieved by using a long vertical column
(fractionating column or tower) attached to the distillation vessel (or boiler)
, Cracking - Correct Answers The process that breaks down complex or heavy
hydrocarbons into simpler or lighter ones by the breaking of C-C and/or H-C bonds using
the combinations of heat, catalysts, and pressure. Must have all 3
monomer - Correct Answers any small molecule that may become chemically bonded into
a larger molecule containing many similar units
Common Monomers - Correct Answers Ethylene, Propylene, Vinyl Chloride, Butadiene,
Styrene, Ethylene Terephthalate
Olefins - Correct Answers synthetic monomers mainly for plastic. Are unsaturated
hydrocarbons containing one double bond C=C bond
Diene (diolefins) - Correct Answers synthetic monomers for rubber. Are unsaturated HCs
containing two double C=C bonds
Polymerization - Correct Answers a process of reacting monomer molecules together in a
chemical reaction to form three-dimensional networks of polymer chains
Homopolymer - Correct Answers Polymers formed with only 1 type of monomers
Copolymers - Correct Answers Polymers formed with 2 or more different types of
monomers
1. Addition polymerization - Correct Answers For homopolyers. Also called chain growth.
Involves rapid chain reaction of chemically activated monomers. Monomers are chained
together at reactive sites (double bonds) through 3 steps:
i. Initiation
ii. Growth
iii. Termination
Condensation Polymerization - Correct Answers for copolymers. Also called step growth.
Involved individual chemical reactions between pairs of reactive monomers. Normally with
water by-product
phenol formaldehyde (PF) - Correct Answers 2 phenol react with 1 formaldyhyde attach to
each other & leave out a water. PF oldest polymer. Thermoset material. AKA Bakelite
Degree of polymerization - Correct Answers the average number (N) of repeating mers in
a polymer molecule (chain)
What is the degree of polymerization for typical commercial polymers - Correct Answers
100-2000
What is the effect of increasing the degree of polymerization? - Correct Answers Degree ↑
TM ↑