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PBT and PET are sensitive to hot water above 60 °C (140 °F). PBT and PET need UV protection if used outdoors, and most grades of these polyesters are flammable, although additives can be used to improve both UV and flammability properties. PBT is produced by the polymerization of 1,4-butanediol and terephthalic acid. [4] [5]
The pre-equilibrium and re-initiation steps are completed very early in the polymerization meaning that the major product of the reaction (the RAFT polymer chains, RAFT-P n), all start growing at approximately the same time. The forward and reverse reactions of the main RAFT equilibrium are fast, favoring equal growth opportunities amongst the ...
In polymer chemistry, chain transfer is a polymerization reaction by which the activity of a growing polymer chain is transferred to another molecule: [1] [2] + + where • is the active center, P is the initial polymer chain, X is the end group, and R is the substituent to which the active center is transferred.
Since the polymerization happens in the crystalline lattice without the aid of solvents or reagents, it comes under the domain of green chemistry. [18] Also, the topochemical polymerizations are mostly atom economical reactions. The product can be obtained without any further purifications.
In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. [1] [2] [3] There are many forms of polymerization [4] and different systems exist to categorize them. IUPAC definition for ...
There is a mode of polymerization referred to as reversible-deactivation polymerization which is distinct from living polymerization, despite some common features. Living polymerization requires a complete absence of termination reactions, whereas reversible-deactivation polymerization may contain a similar fraction of termination as conventional polymerization with the same concentration of ...
All polymerization reactions have three basic steps: initiation, propagation, and termination. The initiation step is the Michael addition of the nucleophile to a monomer . The resultant species undergoes a Michael addition with another monomer, with the latter acting as an acceptor.
Because the chemical reaction of the water with the pipe occurs inside the pipe, it is often difficult to assess the extent of deterioration. The problem can cause both slow leaks and pipe bursting without any previous warning indication. The only long-term solution is to completely replace the polybutylene plumbing throughout the entire building.