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Epoxide monomers may be cross linked with themselves, or with the addition of a co-reactant, to form epoxy; BPA is the monomer precursor for polycarbonate; Terephthalic acid is a comonomer that, with ethylene glycol, forms polyethylene terephthalate. Dimethylsilicon dichloride is a monomer that, upon hydrolysis, gives polydimethylsiloxane.
In 1884 Hilaire de Chardonnet started the first artificial fiber plant based on regenerated cellulose, or viscose rayon, as a substitute for silk, but it was very flammable. [5] In 1907 Leo Baekeland invented the first polymer made independent of the products of organisms , a thermosetting phenol - formaldehyde resin called Bakelite .
A mnemonic is a memory aid used to improve long-term memory and make the process of consolidation easier. Many chemistry aspects, rules, names of compounds, sequences of elements, their reactivity, etc., can be easily and efficiently memorized with the help of mnemonics.
Bullet-proof body armor, helmets, brake pads, ropes, cables and optical fibre cables, etc. and as an asbestos substitute Mylar: Polyethylene terephthalate film: High strength and stiffness, less permeable to gases, almost reflects light completely: Food packaging, transparent covering over paper, reflector for rollsigns and solar cooking stoves ...
Other monomer units, such as formaldehyde hydrates or simple aldehydes, are able to polymerize themselves at quite low temperatures (ca. −80 °C) to form trimers; [3] molecules consisting of 3 monomer units, which can cyclize to form ring cyclic structures, or undergo further reactions to form tetramers, [3] or 4 monomer-unit compounds.
Vinylidene chloride and fluoride can be converted to linear polymers polyvinylidene chloride (PVDC) and polyvinylidene fluoride (PVDF). The polymerization reaction is: n CH 2 =CX 2 → (CH 2 −CX 2) n
It is a synthetic acrylate polymer derived from methyl acrylate monomer. The polymers are colorless. This homopolymer is far less important than copolymers derived from methyl acrylate and other monomers. PMA is softer than polymethyl methacrylate (PMMA), [1] It is tough, leathery, and flexible. [2]
Alternatives include carbonyl allylation with allylmetallic reagents, such as allyltrimethylsilane, [9] [10] [11] or the iridium-catalyzed Krische allylation. Allylation can be effected also by conjugate addition: the addition of an allyl group to the beta-position of an enone. The Hosomi-Sakurai reaction is a common method for conjugate ...