CHEM 1100 Lecture Notes - Lecture 15: Low-Density Polyethylene, Copolymer, Foaming Agent
Document Summary
Polymerization: polyethylene (pe) from ethylene (ethene, cheapest and simplest synthetic polymer. Invented shortly before wwii: two forms, high density (hdpe)--low branching, low density (ldpe)--high branching. Addition polymers: hdpe, ldpe, pp, pvc, ps, no monomer atoms lost, only added to a growing chain, no side products. Intermolecular forces: hydrogen bonding (o-h, n-h, h-f, (london) dispersion forces. Orientation effects: head-to-tail, head-to-tail, cl, h, cl, h, cl, h, most rigid, head-to-head, tail-to-tail. Cl, cl, h, h, cl, cl, h, h. Cl, cl, cl, h, cl, h, h, cl, h. Polystyrene: styrofoam, beads and organic solvent, foaming agent, cfcs, pentane, and co2. Condensation polymers: some atoms from monomer are removed in polymerization, h2o, hcl, ex: pete (pet), a copolymer, copolymer: 2 (or more) monomer types, ethylene = hydroxyl, terephthalic acid = carboxylic acid. Crystallinity: crystalline regions: polymer arranged in a regular array. Durability and rigidity: amorphous regions: polymer regions are random/disordered.
