2,6-Dimethylphenol, copolymerization

Copolymerization of 4-bromo-2,6-dimethylphenol with 2,4,6-trimethylphenol, 4-t-butyl-2,6-dimethylphenol, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 4-hydroxy-3,5-dimethylbenzyl alcohol and a 4-substituted-2,6-di-r-butylphenol are discussed269. 

The telechelica,(i -bis(2,6-dimethylphenol)-poly(2,6-dimethylphenyl-ene oxide) (PP0-20H) [174-182] is of interest as a precursor in the synthesis of block copolymers [175] and thermally reactive oligomers [179]. The synthesis has been accomplished by five methods. The first synthetic method was the reaction of a low molecular weight PPO with one phenol chain end with 3,3, 5,5 -tetramethyl-l,4-diphenoquinone. This reaction occurred by a radical mechanism [174]. The second method was the electrophilic condensation of the phenyl chain ends of two PPO-OH molecules with formaldehyde [177,178], The third method consists of the oxidative copolymerization of 2,6-dimethylphenol with 2,2 -di(4-hydroxy-3,5-di-methylphenyl)propane [176-178]. This reaction proceeds by a radical mechanism. A fourth method was the phase transfer-catalyzed polymerization of 4-bromo-2,6-dimethylphenol in the presence of 2,2-di(4-hy-droxy-3,5-dimethylphenyl)propane [181]. This reaction proceeded by a radical-anion mechanism. The fifth method developed was the oxidative coupling polymerization of 2,6-dimethylphenol (DMP) in the presence of tetramethyl bisphenol-A (TMBPA) [Eq. (57)] [182],... 

A solder resistant high-temperature composition that does not suffer from this drawback has been developed. The blend is composed of poly-(arylene ether) (PAE), PPS, and GFs. The PAE has an intrinsic viscosity (IV) less than or equal to about 0.15 dlg as determined in chloroform at 25°C. The use of the low IV PAE permits improved blending, which leads to improved high-temperature properties. Homopolymers of PAE are those containing 2,6-dimethylphenylene ether units. Suitable copolymers include random copolymers containing, for example, 2,6-dimethylphenylene ether units. In combination with 2,3,6-trimethyl-l,4-phenylene ether units or alternatively, copolymers derived from the copolymerization of 2,6-dimethylphenol with 2,3,6-trimethylphenol. Partially crosslinked PPS, as well as mixtures of branched and linear PPS, may be used in the high-temperature compositions. 

Diphenylphenol and 2,6-dimethylphenol can copolymerize by oxidative coupling. If the diphenyl derivative is polymerized first and subsequently the dimethyl derivative is added to the reaction mixture, block copolymers form. If, however, the order is reversed or both phenols are polymerized together, a random copolymer results. ... 

Dimethylphenol and 2,6-dimethylphenol could be copolymerized using di- -hydroxo-bis[(WA W A -tetramethylethylenediamine)copper(II)] chloride and tetramethylethylenediamine as a catalyst composition [38]. The conversion of the monomers could be followed by gas chromatography. Characterization of the copolymers by IR revealed that the composition of the copolymer could be controlled by the ratio of monomer feeded. 

Polymer II (a sample with [n] 0.35 dl/g) was used as a phenol for copolymerization with 2,6-dimethylphenol. The physical properties of the product (intrinsic viscosities as high as 0.68 dl/g no fractionation of VIII during methylene chloride complex-ation l no long range nmr effects) suggested a block copolymer structure for the product. Since it is likely that polymer II did not redistribute under the mild conditions of polymerization (Table I shows little equilibration with monomer even at 80 ), polymer II was functioning as a monofunctional consonant which did not readily co-equilibrate with the oth r oligomers. Polymer II can be viewed as a chain stopper for reaction (4) and the product can be represented by structure XIII. Colorless, hazy... 

Heitz synthesized polymers with two phenolic end groups by carrying out the polymerization in the presence of a biphenol. Block polyether-polycarbonate and polyether-polyester carbonates were synthesized from these blocks. Percec also prepared a bifunctional PPO by polymerization of 2,6-dimethylphenol in the presence of 2,2 -di(4-hydroxyphenyl-3, 5-dimethylpropane). Etherification of the blocks with chloromethylstyrene gave reactive oligomers that were cross-linkable. When monofunctional PPO was reacted with chloromethyl styrene the resulting styryl-substituted polymers formed comb-like structures on polymerization and could be copolymerized with vinyl monomers. Alternatively, Meijer was able to coredistribute phenol-terminated polymers with PPO to produce block copolymers. ... 

The PPE-MM s were prepared via catalytic oxidative coupling copolymerization between 2,6-dimethylphenol and 4,4 isopropylidenebis(2,6-dimethylphenol) in the presence of a copper-amine based catalyst [6]. Thus materials with number average molecular weights of 2500, 1800, and 900 were prepared and are designated by the acronyms PPE-MM-A, PPE-MM-B, and PPE-MM-C, respectively. The generic structure is depicted in Figure 1. A summary of their properties appears in Table 1. 

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