Poly , polymerization procedure

In summary, our synthetic studies led to the development of interfacial and solution polymerization procedures for the preparation of poly(iminocarbonates) of high molecular weight. These procedures have so far been employed for the synthesis of a small number of structurally diverse poly(iminocarbonates). 

Poly(l,4-naphthylenevinylene) (106) is accessible via the Wessling polymerization procedure. Lenz, Karasz, Wegner et al. have published the synthesis of PNV 106, starting from l,4-bis(chloromethyl)naphthalene [127, 128]. The poly(l,4-naphthylenevinylene) (106) displays an optical absorption energy of 2.05 eV, slightly red-shifted by about 0,3 eV relative to the parent PPV 60-system, due to the electronic effect of the annelated benzene ring. 

As mentioned above, poly(9,10-anthrylenevinylene) is not accessible by means of the Wessling polymerization procedure. Well defined oligo(9,10-anthrylene-vinylene)s (111) were synthesized via Horner-type coupling [132]. Extrapolation of the optical absorption energies in the 111 series against the corres-... 

The corresponding polyiminocarbonates (Figure 5) were prepared first, using recently developed polymerization procedures (5). Poly(Dat-Tym iminocarbonate), the polymer carrying no pendent chains at all, was an insoluble material. Thermal processing techniques could not be used due to the low thermal stability of the polymer in the molten state. Thus poly(Dat-Tyr iminocarbonate) was a virtually non-processible material without practical applications. 

However the formation of thin polymer film on the electrode, i.e. passivation of the electrode, resulted in cessation of the polymerization, which restricted the electro-oxidation as a polymerization procedure. The electro-oxidative polymerization as a method of producing poly(phenyleneoxide)s had not been reported except in one old patent, in which a copper-amine complex was added as an electron-mediator during the electrolysis (4). The authors recently found that phenols are electro-oxidatively polymerized to yield poly-(2,6-disubstituted phenyleneoxide)s, by selecting the electrolysis conditions This electro-oxidative polymerization is described in the present paper. 

Methyl-5-vinyl tetrazole can be readily polymerized in a number of ways to yield high mw soluble polymers or Poly-2-Methyl-5-Vinyl-Tetrazole (PMVT). Again, according to Ref 3 the following polymerization procedure is used for processing the monomer into PMVT ... 

The polymerization procedure is the same as that of poly(2-octyne) catalyst MoClj—EtjSiH. 

Poly(oligoethylene glycol methacrylate) possessing a degree of polymerization of 20 repeat units and a molecular weight 9000 has been targeted in the following polymerization procedure. 

Polymerization Procedure and Characterization. Cyclic ethers and formals were polymerized by adding a measured amount of monomer into the initiator solution at 0°C. The polymer was precipitated with methanol or ethyl ether and freeze-dried from benzene or fractionated by chloroform. The block copolymer of styrene and tetrahydrofuran was dissolved in 1-butanol and refluxed for 12 hours with sodium metal. The solution was washed with water, and the 1-butanol was distilled off. The residual polymer was freeze-dried from benzene, and poly-THF was extracted with 2-propanol in a Soxhlet apparatus. 

A series of 15 wt % isomeric polyimide precursor resin solutions was prepared by the National Aeronautics and Space Administration Langley Research Center. The polymerization procedure has been described previously (2,3). The poly(amic-acid) resin solutions were made from 3,3, 4,4 -benzophenonetetracarboxylic acid dianhydride (BTDA), 4,4 -oxydiphthalic anhydride (ODPA), diaminobenzophenone (DABP), and methylenedianiline (MDA) monomers. 

Ritter et al. have synthesized a variety of (meth)acrylamides in good yields from (meth)acrylic acid and aliphatic and aromatic amines under solvent-free microwave irradiation conditions [14]. It was found that addition of a polymerization initiator (AIBN) to the reaction mixture led directly to poly(meth)acrylamides in a single step. In these polymerization procedures, 11.6 mmol methacrylic acid was mixed with 11.6 mmol amine and 0.58 mmol AIBN in a pressure-resistant test tube. The tubes were sealed and irradiated in a single-mode microwave reactor for 30 min at 140 W (Scheme 14.4). The experiments were performed without temperature control and were not compared with conventional conditions. 

One interesting aspect of this method of producing a suspension polymer is the fact that this method produces beads of poly(vinyl acetate) which may be loosely coated with poly(vinyl alcohol). This coating may be removed much more readily than the poly(vinyl alcohol) used in a conventional polymerization procedure. In the conventional process, a fair amoimt of the suspending agent probably forms a graft copolymer with vinyl acetate and is, therefore, permanently bound to the polymer bead. The properties of the two types of bead polymers are expected to be somewhat different since the graft copolymer with poly(vinyl alcohol) is present only in one and not the other polymer. 

By conventional emulsion polymerization procedures, a crosslinked copolymer of butyl acrylate and 1% allyl methacrylate was formed in the presence of methyl methacrylate. Then additional methyl methacrylate is polymerized in the system. The resultant product was a poly(methyl methacrylate) with improved... 

Summary of the Polymerization Procedure for the Production of a Poly(benzofuran) [110]... 

Poly(4-(terephthaIoyIamino) salicylic acid hydrazide], PTASH was readily synthesized by a low temperature (-5—-lO C) solution (in DMAc) poiycondensation of PASH with TCI. Further detaiis of this polymerization procedure have been presented elsewhere... 

The technique of MIMIC has a number of advantages. First, it allows the use of a liquid precursor, the imprinting solution, which is otherwise difficult with conventional photolithography techniques. Second, the shape and size of MIPs can be readily controlled and altered by those on the stamp. Third, stamps are generally made from poly(dimethyl siloxane) (PDMS), which is transparent to UV light down to 300 nm and it is therefore compatible with the photochemical polymerization procedures employed in MIP synthesis. Fourth, once the master mold is made, the process can be carried out conveniently in a chemical laboratory. No special facility or equipment is needed. 

The synthesis of a well defined poly(vinyl alcohol)-b-poly(aciylic acid) (PVA-PAA) DHBC has been recently reported in the literature [32] by a two step synthetic scheme. First the synthesis of a poly(acrylonitrile) (PAN) block was realized via cobalt-mediated radical polymerization, using a poly(vinyl acetate) (PVAc) macroinitiator, followed by hydrolysis of both blocks. The polymerization was performed in DMF, a very good solvent for PAN, and at low temperature, where block copolymers with low polydispersity were obtained. The polymerization procedure led to well defined macromolecules with relatively high molecular weights. The obtained copolymers were transformed to the desired DHBCs by hydrolysis, using large excess of potassium hydroxide in a water/ethanol mixture. The successful completion of the hydrolysis reaction was monitored by NMR and IR spectroscopy. An additional macroscopical indication of the DHBC formation was the aqueous solubility of the reaction product. 

An electrically conductive polymer composite of polypyrrole and poly(ethyl methacrylate) has been prepared by an emulsion polymerization procedure [ 142]. In this case, the relation between conductivity and the polypyrrole content of the composite exhibited a percolation behavior, with conductivities as high as 6-7 S/ctn. Such composites might be amenable to melt processing for coating formation. Composite films consisting of polypyrrole or poly(N-ethylaniline) filler dispersed in a polyimide matrix have been described for potential use as corrosion control coatings for the A1 alloy AA 2024-T3 [143]. 

In the case of PPy as the conductive core material, a PPy-poly(methyl methacrylate) (PMMA) core-shell nanosphere with an average diameter of several tens of nanometers was synthesized via a two-step microemulsion polymerization procedure (Fig. 4) [213]. The size of core and shell parts was easily tuned by adjusting the amount of surfactant and monomer. The shell thickness was maintained in nanometer-scale to minimize the loss of electrical conductivity. 

The (A) component is eithea- i-PP with <10 wt% comonomer, while (B) is preferably crystallizable C2-C3 copolymer. Blends were mechanically mixed ExxonMobil developed poly(propylene-co-ethylene) Vistamaxx post-metallocene resin. The polymerization procedure Iot the blend component is described in U.S. Patents 5198401 of 30 Mar 1993 and 5057475 of 15 Oct 1991 catalyst system of enhanced productivity, 5153157 of 06 Oct 1992, to Exxon Chem... 

Example 2 Polymerization Procedure for Poly 2,5-bis(3-sulfonatopropoxy)-l,4-phenylene-a/t-l,4-phenylene, 2 (Refer to Scheme 16.1)... 

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