Urea formaldehyde
From Plastics Wiki, free encyclopedia
Urea-formaldehyde is a transparent thermosetting resin or plastic, made from urea and formaldehyde heated in the presence of a mild base such as ammonia or pyridine. These resins are used in adhesives, finishes, and molded objects. Urea-formaldehyde resin has a high tensile strength, flexural modulus and HDT, low water absorption and mould shrinkage and higher surface hardness, elongation at break, and volume resistance.
Urea-formaldehyde foam insulation, or UFFI, was used as cavity-wall insulation beginning in the 1950s. In the 1980s concerns began to develop about the toxic formaldehyde vapor emitted in the curing process, as well as from the breakdown of old foam. Consequently, its use was discontinued.
References
Polyethylenes: Polyethylene (PE), Low density polyethylene (LDPE), High density polyethylene (HDPE), Linear low density polyethylene (LLDPE), Crosslinked polyethylene (XLPE), Ultra High Molecular Weight Polyethylene (UHMWPE)
Other Polyolefins: Polypropylene (PP), Biaxially-oriented polypropylene, Polybutylene (PB), Polyisobutene (PIB)
Polyacrylates: Polymethyl methacrylate (PMMA), polymethyl acrylate (PMA), hydroxyethyl methacrylate (HEMA), Sodium polyacrylate
Polystyrenes: Polystyrene (PS), High impact polystyrene (HIPS), Extruded polystyrene (XPS), Expanded Polystyrene
Polyesters: Polyethylene terephthalate (PET)
Polysulfones: Polysulfone (PSU), Polyarylsulfone (PAS), Polyethersulfone PES, Polyphenylsulfone (PPS)
Polyamides: Polyamide (PA), polyphthalamide (PPA), Bismaleimide (BMI), urea formaldehyde (UF)
Polyurethanes: Polyurethane (PU), Polyisocyanurate (PIR)
Chloropolymers: Polyvinyl chloride (PVC), Polyvinylidene dichloride (PVDC)
(Chloro)fluoropolymers: Fluoropolymer (FE), Polytetrafluoroethylene (PTFE), Polyvinylidene difluoride (PVDF), Polychlorotrifluoroethlyene (PCTFE), Ethylene chlorotrifluoroethlyene (ECTFE)
Other Homopolymers: Polycarbonate (PC), Polylactic acid (PLA), Polyacrylamide (PAM), Polyetheretherketone (PEEK)
Other Copolymers: Acrylonitrile butadiene styrene (ABS), Polybutadiene acrylonitrile (PBAN)
