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Preparation of poly

Anti L, Goodwin J W, Flill R D, Ottewill R FI, Owens S M, Papworth S and Waters J A 1986 The preparation of poly (methyl methaorylate) lattioes in non-aqueous media Colloid Surf. 17 67-78... [Pg.2690]

Polyphenylene polymers can be prepared by this coupling. For example, the preparation of poly(/i-quaterphenylene-2,2 -dicarboxylic acid) (643) was carried out using aqueous NaHCO and a water-soluble phosphine ligand (DPMSPP)[5I I]. Branched polyphenylene was also prepared[5l2). [Pg.219]

Vinyl chloride is an industrial chemical produced in large amounts (10 ° Ib/year in the United States) and is used in the preparation of poly(vmyl chloride) Poly(vinyl chio ride) often called simply vinyl has many applications including siding for houses wall coverings and PVC piping... [Pg.190]

The sedimentation and diffusion coefficients for three different preparations of poly(methyl methacrylate) were measuredf in /i-butyl chloride at 35.6 C (= 0) and in acetone at 20 C (> 0) and the following results were obtained ... [Pg.656]

Synthesis and Properties. The synthesis of (21) follows a very straightforward route based on readily accessible starting materials and on some novel reactions ia organo—inorganic sulfur chemistry (83—85), as well as on polycondensation chemistry analogous to that utilized ia the preparation of poly(alkyl/arylphosphazenes). One preparation of (21) is as follows ... [Pg.261]

The above mentioned new heterocyclic systems have not been used in the preparation of poly(aryl sulfides). The authors reported [57] a polyheteroarylene sulfide by the reaction between 2,6-dichloropyridine and sodium sulfide. [Pg.39]

Tsuda156 reported the preparation of poly(vinyl 2-furylacrylate) by the reaction of 2-furylacrylyl chloride with poly(vinylalcohol) in NaOH-water-methyl ethyl ketone. Up to 80% of the hydroxyl groups were esterified. The interest of this technique is obvious here, considering that the vinyl ester of 2-furylacrylic acid does not polymerize119 A similar procedure was employed by Gandini and Rieumont26,1 9 for the synthesis of poly(vinyl 2-furoate) another product unobtainable via a standard polymerization process (see Section 1II-B-3). [Pg.85]

By using a similar procedure for the preparation of hybrids of silica, hybrids materials consisting of other metal oxides were also prepared by the group of Wilkes [15]. For example, titania was incorporated into organic polymers by using the chemically controlled condensation (CCC) method for the preparation of poly(tetramethylene oxide)-silica or poly(dimethylsiloxane)-silica hybrids. Especially, in the case of the hybrid with poly (tetramethylene oxide), the modulus or ultimate strength of the hybrid increased in the presence of titania component, as shown in Table 3. This phenomenon was explained by the catalytic ability of... [Pg.15]

The preparation of poly( -caprolactone) given below is a bulk ring-opening polymerization of -caprolactone initiated by Ti(OBu)4 in the presence of... [Pg.98]

ADMET polymers are easily characterized using common analysis techniques, including nuclear magnetic resonance ( H and 13C NMR), infrared (IR) spectra, elemental analysis, gel permeation chromatography (GPC), vapor pressure osmometry (VPO), membrane osmometry (MO), thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC). The preparation of poly(l-octenylene) (10) via the metathesis of 1,9-decadiene (9) is an excellent model polymerization to study ADMET, since the monomer is readily available and the polymer is well known.21 The NMR characterization data (Fig. 8.9) for the hydrogenated versions of poly(l-octenylene) illustrate the clean and selective nature of ADMET. [Pg.442]

There are four different industrial routes to the preparation of poly (ethylene), and they yield products having slightly different properties. The four routes are ... [Pg.6]

Preparation of poly(dichlorophosphazene), (NPCl2)n> a polymeric intermediate from which the great majority of POPs have been prepared by nucleophilic substitution of the highly reactive chlorine atoms with carefully selected organic substituents... [Pg.169]

This ROP of hexachlorocyclophosphazene to polydichlorophosphazene is very relevant in phosphazene chemistry as it has been used in almost every laboratory in the world for the preparation of poly(organophosphazenes) starting from the middle of the 1960s up to recent times [38]. H. R. Allcock discovered in 1965 [40-42] that (NPCl2)3 can open its inorganic ring thermally, under strictly controlled experimental conditions (250 °C, vacuum of 10" torr, and reaction time of 8-12 h), to form polydichlorophosphazene in a reasonable yield, but in a rather slow and irreproducible way [38]. Moreover, the final polymer obtained shows a very variable MW and MW distribution, with a strong tendency to produce crosslinked materials [45]. [Pg.172]

World Health Organization 10th Annual Report, 1981, pp. 62-63. World Health Organization 11th Annual Report, 1982, p. 61. Heller, J., Penhale, D. W. H., and Helwing, R. F., Preparation of poly(ortho esters) by the reaction of ketene acetals and polyols, J. Polym. Sci., Polym. Lett. Ed., 18, 82-83, 1980. [Pg.159]

Heller, J., Ng, S. Y., and Penhale, D. W. H., Preparation of poly(carboxy-ortho esters) by the reaction of diketene acetals and carboxylic acids. In Preparation. [Pg.160]

In analogy to the transesterification of diethyl terephthalate used in the preparation of commercially important polyester fibers such as Dacron (24), a transesterification reaction waus successfully employed for the preparation of poly(N-acylhydroxyproline esters) (Scheme 1). [Pg.202]

Perhaps the most interesting finding of our synthetic studies was that the interfacial preparation of poly(iminocarbonates) is possible in spite of the pronounced hydrolytic instability of the cyanate moiety (see Illustrative Procedure 3). Hydrolysis of the chemically reactive monomer is usually a highly undesirable side reaction during interfacial polymerizations. During the preparation of nylons, for example, the hydrolysis of the acid chloride component to an inert carboxylic acid represents a wasteful loss. [Pg.217]

In contrast, during the interfacial preparation of poly(iminocar-bonates), the hydrolysis of the dicyanate component regenerates the diphenol component, which is a necessary reactant. Consequently, it is possible to obtain poly(iminocarbonates) simply by the controlled hydrolysis of a dicyanate under phase transfer conditions. [Pg.217]

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). [Pg.219]

Zhou, Q. X., and Kohn, J., Preparation of poly(L-serine ester) A structural analog of conventional poly-L-serine, Macromole-cules. In Press. [Pg.227]

M[TpRR ] complexes (M = Li, Na, Cs, R4N+) may also be obtained by the reactions of the monoprotonated derivative H[TpRR ] with MOH (lb). Both the M[TpRR] and M[BpRR] complexes are useful starting materials for the preparation of poly(pyrazolyl)borato complexes of both the transition and main group metals. [Pg.298]

The Preparation of MM-b-MA and MM-b-MA.K. Inspired by the unexpected selectivity of the reaction of TMSI with S-b-MM and S-b-tBM, we decided to attempt the preparation of poly(methyl methacrylate-b-t-butyl methacrylate) (MM-b-tBM) and its unprecedented conversion to MM-b-MA. [Pg.288]

In an attempt to identify new, biocompatible diphenols for the synthesis of polyiminocarbonates and polycarbonates, we considered derivatives of tyrosine dipeptide as potential monomers. Our experimental rationale was based on the assumption that a diphenol derived from natural amino acids may be less toxic than many of the industrial diphenols. After protection of the amino and carboxylic acid groups, we expected the dipeptide to be chemically equivalent to conventional diphenols. In preliminary studies (14) this hypothesis was confirmed by the successful preparation of poly(Z-Tyr-Tyr-Et iminocarbonate) from the protected tyrosine dipeptide Z-Tyr-Tyr-Et (Figure 3). Unfortunately, poly (Z-Tyr-Tyr-Et iminocarbonate) was an insoluble, nonprocessible material for which no practical applications could be identified. This result illustrated the difficulty of balancing the requirement for biocompatibility with the need to obtain a material with suitable "engineering" properties. [Pg.158]

For the preparation of poly(methacrylamide), the poly(methacrylic acid) is converted with CDI into a polymer imidazolide, which reacts with an amine to give the corresponding polyamide [156M157]... [Pg.126]

Other lignins can be reacted with this chemistry. Table 7 shows synthesis data for the preparation of poly(lignin-g-(1-amido-ethylene)) from several different lignins. Sample 1 is a kraft pine lignin grafted in a reaction coinitiated with sodium chloride. [Pg.198]

The preparation of poly(m-carborane-siloxane) polymers has also been successfully achieved directly from the carborane monomer.22 The reaction used is shown in scheme 9. Here, the direct salt elimination reaction between dilithiocarborane and a dichlorosiloxane (e.g., 1,5-dichlorohexamethyltrisiloxane) results in the formation of linear polymers with a molecular-weight (M ) typically of 6800 dalton. However, the reported literature detailing this approach is very limited indeed, and the reaction has not found significant use. This is most probably because only relatively low molecular-weight polymers can be produced, ultimately restricting the flexibility to produce materials of controlled mechanical properties. [Pg.105]

Takafuji, M., Ide, S., Ihara, H. and Xu, Z.H. (2004) Preparation of poly(l-vinylimidazolej-grafted magnetic nanoparticles and their application for removal of metal ions. Chemistry of Materials, 16 (10), 1977-1983. [Pg.84]

Kennett, F. A. et al., J. Chem. Soc., Dalton Trans., 1982, 851-857 In attempted preparation of poly(selenium nitride), the black solid formed by interaction with selenium tetrabromide in acetonitrile exploded violently within 1 min at 0°C. The solid produced from diselenium tetrachloride in acetonitrile exploded at around 100°C, and in dichloromethane the product exploded in contact with a nickel spatula. [Pg.464]

Nakayama Y., Miyamura M., Hirano Y., Goto K., Matsuda T., Preparation of poly(ethylene glycol)-polystyrene block copolymers using photochemistry of dithiocarbamate as a reduced cell-adhesive coating material, Biomaterials 1999 20 963-970. [Pg.500]


See other pages where Preparation of poly is mentioned: [Pg.51]    [Pg.537]    [Pg.289]    [Pg.399]    [Pg.51]    [Pg.39]    [Pg.14]    [Pg.9]    [Pg.818]    [Pg.24]    [Pg.58]    [Pg.203]    [Pg.204]    [Pg.97]    [Pg.256]    [Pg.154]    [Pg.62]    [Pg.283]    [Pg.143]   
See also in sourсe #XX -- [ Pg.99 ]




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B Preparation of Poly(l-pyrazolyl)borates

Poly , preparation

Poly and derivatives preparation of monomer

Poly methods of preparation

Poly prepared

Poly(organophosphazene)s Prepared by Macromolecular Substitution of

Preparation of Gas Sensors Based on Poly (pyrrole) Films

Preparation of Isotactic and Syndiotactic Poly(Methyl Methacrylate) with Butyllithium in Solution

Preparation of Poly(2,6-dimethylphenylene ether)

Preparation of Poly(a)-Methylstyrene

Preparation of Poly(vinyl Alcohol)

Preparation of Poly(vinylbutyral)

Preparation of poly(alkenoic acid)s

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