Polymers Flashcards
Nylon - 6,6 monomer
Hexamethylene diamine and adipic acid
Nylon - 6,6 polymer type
Condensation polymer
polythene polymer type
Addition polymer
Rayon
Cellulose acetate
Classification based on source
Natural, semi-synthetic, synthetic
Natural polymers
Cellulose, rubber, starch, resins, proteins
Semi-synthetic polymers
Rayon, cellulose nitrate, cellulose xanthate
Synthetic polymer
Polythene, Nylon - 6,6, Buna-S
Synthetic rubber
Buna-S
Classification based on structure
Linear, branched chain, cross linked/network
Linear polymers
High density polythene, PVC, polyester
Branched chain polymer
Low density polythene
Cross linked/network polymers
Bakelite, melamine
Bonding in cross linked polymers
Strong covalent bonds
Cross linked polymers are formed from
bi-functional and tri-functional monomers
Classification based on mode of polymerisation
Addition polymers (homo+co), Condensation polymers
Buna-S
Styrene + 1,3-Butadiene
Homopolymers
Polythene
Copolymers
Buna-S, Buna-N
Condensation polymers
terylene(dacron), nylon-6,6, nylon-6
Classification based on molecular forces
Elastomers, fibers, thermoplastic polymers, thermosetting polymers
Elastomers
Weak van der Wall forces (Buna-S, Buna-N, neoprene)
Fibers
Strong hydrogen bonding, crystalline (polyamide, polyester)
Polyamide
Nylon-6,6
Polyester
Terylene/dacron
Thermoplastic
Intermolecular forces are in between elastomers and fibers, no cross linking, capable of softening on heating and hardening on cooling (polythene, polystyrene, polyvinyls)
Thermosetting
Heavily branched and cross linked, infusible 3D network solid, cannot be reused (Bakelite, urea formaldehyde resin)
Classification based on growth of polymer chain
Addition/Chain growth polymer, Condensation/step growth polymer
Addition/chain growth polymers
LDP, HDP, PTFE(Teflon), Polyacrylonitrile(PAN)
Condensation/step growth Polymers
Terylene/dacron(polyester), Nylons(polyamides), Novolac, Bakelite (Phenol+formaldehyde), Melamine(Melamine+formaldehyde)
Copolymerisation
Styrene butadiene rubber (SBR is more flexible than polybutadiene and tougher than polystyrene(homopolymers))
Natural rubber
Linear hydrocarbon polymer of isoprene (cis-1,4-polyisoprene)
Natural rubber is soluble in
Non polar solvent
Vulcanization of natural rubber
Rubber+ sulphur(5%) at 373 to 415K, Sulphur froms cross links at double bond sites, rubber becomes more hard and flexible
Synthetic rubber
Neoprene, Buna-N
Neoprene
Chloroprene
Buna-N
1,3-butadiene+acrylonitrile
Molecular mass of polymers
Always expresed as an average
Molecular mass of natural polymers (proteins)
Molecular masses are singular and not expressed as average
Biodegradable polymers
Nylon-2-Nylon-6, Polybetahydroxybutyrate-co-p-hydroxyvalerate(PHBV)
Nylon-2-Nylon-6
Glycine+Amino caproic acid
PHBV
3-Hydroxybutanoic acid + 3-Hydroxypentanoic acid
Glyptal
Ethylene glycol+Phthalic acid
Orlon/Acrilan
Vinyl cyanide (polyacrylonitrile)
Terylene/dacron/mylar
Ethane-1,2-diol + Terephthalic acid
Nylon-6
Caprolactum
Gutta-Percha
Trans- polyisoprene, non elastic, non crystalline
Nylon-6-Nylon-10
Hexamethylene diamine + Sebacic acid
Dynel
Copolymer of acrylonitrile and vinyl chloride
Thiokol
1,2-dichloroethane