Synthesis of the Monomers

Hexafluoro-2-(4-fluorophenyl)-2-propyl acrylate (la) and hexafluoro-2-(4-fluorophenyl)-2-propyl methacrylate (lb) were prepared by gradually adding a solution of 0.06 mol of acryloyl or methacryloyl chloride, respectively, in 20 ml of tetrahydrofuran (THE), to a cooled solution of 0.04 mol of HFAF in 50 ml of THF containing 0.06 mol of triethylamine. The mixture was stirred for 10-12 h at room temperature it then was poured into 200ml of water, and the new product was extracted with diethyl ether. After the diethyl ether was evaporated, the crude product was purified by column chromatography using a mixture of hexane and dichloromethane (1 1 by volume) as the elution solvent. Distillation afforded la, b.p. 72-74°C/10 mm Hg, and Ib, b.p. 48-52°C/10 mm Hg. 

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Although poly(trimethylene terephthalate) has been known for many years it was only introduced by Shell in the late 1990s as a consequence of a breakthrough in the synthesis of the monomer 1,3-propane diol which enabled the polymer to be produced at costs suitable for commercialisation. The polymer itself is prepared by melt condensation of the diol with terephthalic acid. 

Synthesis of Disulfide-Bridged Collagen Peptide 34 1 691 Synthesis of the Monomer 29 ... 

The synthesis of the monomers 4-6 has been achieved by the following route ... 

Overall, the most difficult part of the ADIMET process is the synthesis of the monomers. Monomer synthesis can be a challenge, considering that the necessary aromatic diiodides... 

Fossil based raw materials, mainly oil, gas and occasionally coal, are used almost exclusively for the manufacture of monomers. Plant materials, the so-called renewable resources, have been used earlier and could become more significant once again in the future. Although the plastics in these cases are obtained by direct polymerization of their monomers, the synthesis of the monomers themselves often requires several intermediate steps. The multi-functional multiple intermediate compounds in the plastic synthesis steps cannot be clearly defined as monomers in every case. The poly-con-... 

The manufacture of polyvinyl chloride is still very important com-mercially8,45-47 and the synthesis of the monomer is therefore an important step in this synthesis (see Section 13.2) ... 

The synthesis of the monomer for Cyclotene resins (Equation 13) is accompanied by the formation of by-products that derive from internal rather than terminal aryl attack on the vinyl group. Further decrease of selectivity is caused by aryl attack on only one of the terminal carbon atoms of the two siloxane vinyl groups and by hydrogenolysis at the C-Si bond carbons, followed by aryl group attack on the terminal or the internal carbon atom of the vinyl group thus formed. 

Example 12.1 Poly (methyl methacrylate) is used in the manufacture of resins and plastics. The traditional synthesis of the monomer, methyl methacrylate, uses acetone and hydrogen cyanide as reagents, followed by the acidic hydrolysis and esterification of the nitrile group, as shown below ... 

Figure 9.56 Synthesis of the monomer sets M2-M3 used for the synthesis of the SP peptidomimetic encoded pool chiral selector library L38.

ADMET polymers containing D-chiro-inositol have been prepared by polymerizing the acetonide-protected inositol diene followed by deprotection to the D-c/z/ro-inositol containing polymer [171]. Synthesis of the monomer precursor was performed using whole-cell fermentation of bromobenzene with... 

Anhydrohexitol nucleic acids (HNA) have received much attention, but the synthesis of the monomers is difficult. In search for better and synthetically easier... 

The synthesis of the monomers as well as the polymerization of PFSA membranes involve dangerous reactions under conditions of high pressure and temperature. Additionally, the synthesis of the comonomer that is commonly referred to as perfluorosulfonylfluoride ethyl propyl vinyl ether (PSEPVE) involves numerous steps with low yields. These factors contribute to the cost of these materials. The synthesis routes described in detail by Doyle and Rajendran are summarized here. The synthesis of the long-chain PFSA monomers used in commercial systems like Nafion, Flemion, and Aciplex proceeds through... 

The preparation of a poly-a-amino acid involves first, synthesis of the monomer, and secondly its polymerization. We are mainly concerned here with the latter aspect. Methods of monomer synthesis commonly follow one of two alternative routes viz. reaction of the a-amino acid with phosgene (1) or cyclization of an N-alkoxy carbonyl derivative of the a-amino acid by treating with SOCI2, PCI5 or similar reagents (2). 

The number of supramolecular polymers based on very strong multiple hydrogen-bonded units is relatively small because of the increased synthetic efforts required for the synthesis of the monomers. Intriguing architectures such as nanotubes88 are obtained... 

Seela and co-workers have synthesised DNA in which xylose entirely replaces ribose sugar.To achieve this the synthesis of the monomer reagents has been... 

Subsequently, Hedrick et al. also prepared a monomer that contains two different reactive sites, allowing for the polymerization of a single monomer by two different mechanisms [366]. The synthesis of the monomer is shown in Scheme 62. The 4-(acryloyloxy)-e-caprolactone was then polymerized via an ATRP mechanism with NiBr2(PPh3)2 as the catalyst at 90 °C to yield polymers with Mn=3500-24,000 with Mw/Mn=1.13-1.30. 

Figure 2. Synthesis of the monomers OHMSS, MOPSS, and EOMSS.

Synthesis of the monomer-template conjugate is often troublesome and less economical. 

Synthesis. Polymers containing the vinyl-benzyl phosphonium unit can be made by either direct synthesis of the monomers and subsequent polymerization or phosphonation of chloromethyl styrene containing polymers. The latter is preferred due to the difficulty of obtaining the vinyl benzyl phosphonium monomer in good yield and purity without spontaneous polymerization. In either case, synthesis of elastomers containing quaternary phosphonium salts have not been reported to date. 

Accessible precursor architectures (building imits, dimensionality of the polymer molecule) are dictated by the methods of the chemical synthesis of the monomer units and the associated polymerization reactions. The type of shape-forming procedure used (fiber-extrusion firom solution or melt, spincoating, etc.) engenders constraints on what is considered useful polymer rheology. Especially in the case of fiber-drawing or -extrusion the precursor should exhibit thixotropic or non-Newtonian viscoelastic behavior. The viscosity should be sufficiently high at zero shear such that once formed, the material will retain its new shape. 

The industrial preparation of the polymer, polyftetrafluoroethene) or PTFE, is based on the synthesis of the monomer teoafluoroethene, CF2=CFj, which is prtxiuced by thermal cracking of chlorodifluoro-methane, CHClFj, according to reaction (1) below,... 

Details A liquid, a by-product in the synthesis of the monomer vinylidene chloride. 

Synthesis of the monomer 3 Method I 4-VPy was added to a hot ethanol solution of CoCU after cooling the crystal adduct was isolated and dried over NaOH in a desiccator. 

For synthesis of the monomer, chloral (trichloro acetaldriiyde), see reference (2). 

Scheme 2. The synthesis of the monomer M-5 used in the preparation of embedded donor type NLO polyimides.

As mesogenic groups, 4 -trifluoromethoxy-azobenzene units are used and linked to the methacrylate main chain by alkylene spacer, where the number n of the spacer groups was varied from 2 to 6. The chemical structure of the repeating unit of the polymers PM (n=2-6) is given in Figure 1. Details of the synthesis of the monomer, the condition for the radical polymerization, and the determination of the molecular masses were reported elsewhere 19,20). The phase transition temperatures of the polymers were... 

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