Alkyl Vinyl Ethers Research Articles

Star‐shaped polymers by living cationic polymerization. VII. Amphiphilic graft polymers of vinyl ethers with hydroxyl groups: Synthesis and host–guest interaction

AbstractAmphiphilic graft polymers of vinyl ethers (VEs) (6) where each branch consists of a hydrophilic polyalcohol and a hydrophobic poly(alkyl vinyl ether) segment were prepared on the basis of living cationic polymerization, and their properties and functions were compared with the corresponding amphiphilic star‐shaped polymers. In toluene at −15°C, the HI/ZnI2‐initiated living block polymer 2 of an ester‐containing VE (CH2CHOCH2CH2OCOCH3) and isobutyl VE (IBVE) was terminated with the diethyl 2‐(vinyloxy)ethylmalonate anion [3; ΦC(COOEt)2CH2CH2OCH  CH2] (2/3 = 1/2 mole ratio) to give a macromonomer (4), H[CH2CH(OCH2CH2OCOCH3)] m‐[CH2CH(OiBu)]nC(COOEt)2CH2CH2OCH  CH2 (m = 5, n = 15; M̄n = 2600, M̄w/M̄n = 1.13, 1.10 vinyl groups/chain). Subsequently, 4 was homopolymerized with HI/ZnI2 in toluene at −15°C. In 3 h, 85% of 4 was consumed and a graft polymer (5) was obtained [M̄w = 15000, DPn (for 4) = 6]. The apparent M̄w (10,900) of 5 by size‐exclusion chromatography (SEC) is smaller than that by light scattering as well as that (18,300) by SEC of the corresponding linear polymer with the almost same molecular weight, indicating the formation of a multi‐branched structure. Hydrolysis of the pendant esters in 5 gave the amphiphilic graft polymer 6 where each branch consists of a hydrophilic polyalcohol and a hydrophobic poly(IBVE) segment. The graft polymer 6 was found to interact specifically with small organic molecules (guests) with polar functional groups, and 6 differed in solubility and host‐guest interaction from the corresponding star‐shaped polymer. © 1993 John Wiley & Sons, Inc.

On the application of an association model to blends containing poly(hydroxy ether of bisphenol A)

The possibilities and shortcomings of the Painter-Coleman association model (PCAM) to predict some thermodynamic properties of polymer blends are explored. More specificity, enthalpies of mixing, excess heat capacities, melting point depressions in crystalline/amorphous blends, and the evolution of the T g with blend composition are simulated for blends of phenoxy (a copolymer of Bisphenol A and epichlorohydrin) (PH) with families of polymers, including poly(alkylene oxides), poly(vinyl alkyl ethers), aliphatic polyesters, and polymethacrylates. Results are compared with some previously reported experimental data

Star‐shaped polymers by living cationic polymerization, 6. Amphiphilic star‐shaped block copolymers of vinyl ethers with carboxyl groups: synthesis and host‐guest interaction

AbstractAmphiphilic star‐shaped polymers (5 and 6) of vinyl ethers (VEs), the arms of which consist of apoly(carboxylic acid)/poly(alkyl VE) AB block copolymer, were prepared on the basis of living cationic polymerization. Thus, a sequential living polymerization of a VE with a pendant malonate group [CH2  CHOCH2CH2CH(COOCH2CH3)2] and and isobutyl VE with HI/ZnI2 at −15°C in toluene led to a living block copolymer (3a), which was subsequently allowed to react with a small amount of a bifunctional vinyl ether [1; CH2  CHOCH2CH2OC6H4C(CH3)2‐C6H4OCH2CH2OCH  CH2] to give a star‐shaped block copolymer (4a). Alkaline hydrolysis of the ester functions of 4a, followed by neutralization, gave the amphiphilic star copolymer (5a, diacid form; \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm \{ H\rlap{--} [CH}_2 {\rm CH(OCH}_2 {\rm CH}_2 {\rm X)\rlap{---} ]}_m {\rm \rlap{--} [CH}_2 {\rm CH(O}i{\rm Bu)\rlap{--} ]}_n \} _f - {\rm (core)}, $\end{document} X = CH(COOH)2) with hydrophilic poly(carboxylic acid) segments in the outer region, and subsequent decarboxylation led to the monoacid form 6a (X = CH2COOH). Amphiphilic star copolymers (5b and 6b; \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm \{ H\rlap{--} [CH}_2 {\rm CH(O}i{\rm Bu)\rlap{---} ]}_m {\rm \rlap{--} [CH}_2 {\rm CH(OCH}_2 {\rm CH}_2 {\rm X)\rlap{--} ]}_{n'} \} _f - {\rm (core)}, $\end{document} 5b: X = CH(COOH)2, 6b: X = CH2COOH) with an opposite segment sequence(inner polyacid chains) were also prepared. The star copolymer 5b (m′ = 30, n′ = 10) was insoluble in methanol, in which the polymer 5a (m = 10, n = 30) with the opposite segment sequence was soluble, and both 5a and 5b as well as both 6a and 6b differed in solubility from the corresponding linear polymer. The amphiphilic polymers 5 and 6 were also found to interact selectively with guests with polar functional groups such as benzoic acid and benzylamine.

Preparation and properties of poly(alkyl vinyl ether‐2‐ethyl‐2‐oxazoline) diblock copolymers

AbstractA method for the synthesis of well‐defined poly(alkyl vinyl ether–2‐ethyl‐2‐oxazoline) diblock copolymers with hydrolytically stable block linkages has been developed. Monofunctional poly(alkyl vinyl ether) oligomers with nearly Poisson molecular weight distributions were prepared via a living cationic polymerization method using chloroethyl vinyl ether together with HI/ZnI2 as the initiating system and lithium borohydride as the termination reagent. Using the resultant chloroethyl ether functional oligomers in combination with sodium iodide as macroinitiators, 2‐ethyl‐2‐oxazoline was polymerized in chlorobenzene/NMP to afford diblock copolymers. A series of poly(methyl vinyl ether–2‐ethyl‐2‐oxazoline) diblock materials were found to have polydispersities of ≈ 1.3–1.4 and are microphase separated as indicated by two Tg's in their DSC thermograms. These copolymers are presently being used as model materials to study fundamental parameters important for steric stabilization of dispersions in polar media. © 1993 John Wiley & Sons, Inc.

New views on cationic polymerizations induced by ionizing radiations

This paper is about a reinterpretation of the cationic polymerizations of hydrocarbons (HC) and of alkyl vinyl ethers (VE) by ionizing radiations in bulk and in solution. It is shown first that for both classes of monomer, M, in bulk ([M] = mB) the propagation is unimolecular and not bimolecular as was believed previously. This view is in accord with the fact that for many systems the conversion, Y, depends rectilinearly on the reaction time up to high Y. The growth reaction is an isomerization of a rc-complex, P+nM, between the growing cation P+nand the double bond of M. Therefore the polymerizations are of zero order with respect to m, with first-order rate constant k+p1. The previously reported second-order rate constants K+pare related to these by the equation K+p≡ K+pmBIf the monomer contains a group, other than the double bond, that can complex with the carbenium ion, such as an aromatic ring or a heteroatom, the resulting complexes, P+nG, are not propagators; in such systems the concentration of the propagators, [P+nM], is less than the total concentration, c, of cations. This newly recognized effect makes the k+p1of most monomers calculated from c too small; it may be at least partly responsible for the rate of polymerization of styrene being significantly less than that of isobutene, and for the rate of polymerization of the VE being much less than that of the HC.

Asymmetric syntheses of substituted dehydropyrans by Diels-Alder heterocycloadditions involving chiral vinyl ethers as dienophiles

The alkyl vinyl ethers 2b–8b (deriving from the alcohols 2a–8a) smoothly reacted with methyl E-benzylidenepyruvate 1 in the presence of catalytic amounts of Eu(fod) 3, thus leading to the endo cycloadducts 9–15 in high yields. The cycloadducts 12–15 were obtained with moderate to good diastereomeric excesses (43–72%). Thus the vinyl ether 8b deriving from methyl (R)-mandelate gave the endo adduct 15 in 83% yield and with 72% diastereomeric excess.

Molecular Engineering of Liquid Crystal Polymers by Living Polymerization. XXIII. Synthesis and Characterization of AB Block Copolymers Based on ω-[(4-Cyano-4′ -Biphenyl)-oxy]alkyl Vinyl Ether, 1H, 1H, 2H, 2H-Perfluorodecyl Vinyl Ether, and 2-(4-Blphenyloxy)ethyl Vinyl Ether with 1H, 1H, 2H, 2H-Perfluorodecyl Vinyl Ether

Abstract This paper describes the synthesis and characterization of AB block copolymers based on ω-[(4-cyano-4′-biphenyl)oxy]alkyl vinyl ether (6-n), with alkyl being ethyl (6-2), propyl (6-3), nonyl (6-9), and undecanyl (6-11), with 1H, 1H, 2H, 2H-perfluorodecyl vinyl ether (CF8), poly[(-6-n)-b-CF8]X/Y (where X/Y refers to the weight ratio of the two segments), and of 2-(4-biphenyloxy)ethyl vinyl ether (BEVE) with 1H,-1H, 2H, 2H-perfluorodecyl vinyl ether, poly[BEVE-b-CF8]X/Y. They were prepared by living cationic polymerization and exhibit a narrow molecular weight distribution. All block copolymers display a micro-phase-separated morphology when the A segment is in the liquid crystalline phase. Block copolymers based on 6-2, 6-3, and BEVE with CF8 also exhibit a microphase-separated morphology in the melt phase of A and B blocks.

Molecular engineering of liquid crystalline polymers by living polymerization. XVII. Characterization of poly{10‐[4‐cyano‐4′‐biphenyl)oxy]decanyl vinyl ether}s by 1‐D and 2‐D 1H‐NMR spectroscopy

Abstract : Since the first examples of mesogenic vinyl ethers and liquid crystalline poly(vinyl ether)s were reported from our laboratory, several research groups became actively engaged in the synthesis of liquid crystalline poly(vinyl ether)s mainly because they can be polymerized by living cationic mechanism. So far, we have elucidated the influence of molecular weight on the phase transitions of poly(omega-((4-cyano-4'-biphenyl)oxy)alkyl vinyl ether)s with alkyl groups from ethyl to undecanyl. Binary copolymerization experiments performed with the same monomers at constant copolymer molecular weight allowed the molecular design of nematic, smectic A and reentrant nematic mesophases. Similar homopolymerization and copolymerization experiments were used to tailor make polymers exhibiting a chiral smectic C mesophase. In addition, it has been shown that many functional mesogenic vinyl ethers can be polymerized by our preferred initiating system CF3SO3H/S(CH3)2 in CH2Cl2(9). The experiments described so far required only a good control over the degree of polymerization and polydispersity of the polymer.

Partial Esters of Alternating Copolymers of Maleic Anhydride and Alkyl Vinyl Ethers for Pharmaceutical Applications

The synthesis, characterization, and reactivity of alternating copolymers of maleic anhydride (MA) with new vinyl ethers of mono-O-methyl oligoethylene glycol (MePegnVE, degree of oligomerization n = 1-4) are described. The linear MA/PegnVE copolymers were partially esterified with alcohols such as methanol, ethanol, n-butanol, methoxyethanol, and n- dodecanol. Depending upon the nature of the two reactive components, the degree of esterification was between 10 and 70%. Semiquantitative indications on the relative reactivity of both polymeric materials and alcohols are pro vided. The potential of this new class of functional polymers is to provide am phiphilic polymeric ionomers as candidates for drug controlled release, based on their biocompatibility.

Synthesis and characterization of poly(alkyl vinyl ether)/poly(ϵ-caprolactone) diblock copolymers

This paper reports the synthesis and characterization of hydroxyl functionalized poly(butyl vinyl ether) oligomers, and block copolymers comprised of poly(butyl vinyl ether) and poly(ϵ-caprolactone). Using the HI/ZnI2 initiating system in toluene at −20°C, monofunctional poly(butyl vinyl ether) oligomers of predicted molecular weights precisely terminated with aldehyde or primary hydroxyl endgroups have been prepared. Furthermore, the primary hydroxyl end functionality has been utilized to initiate ring opening polymerization of ϵ-caprolactone in the presence of stannous octanoate as the catalyst. This ring opening reaction provides an entry into new poly[(butyl vinyl ether)-block-poly(ϵ-caprolactone)] copolymers.

A New Versatile Synthesis oftert-Butyl 2-Alkoxycyclopropanecarboxylates1

Bromination of alkyl vinyl ethers 1 and subsequent reaction of the resulting dibromides 2 with tert-butyl lithioacetate leads to tert-butyl 3-alkoxy-4-bromobutanoates 3 in good to very good yields. By treatment of 3 with bases such as potassium tert-butoxide, lithium diisopropylamide and lithium hexamethyldisilazide, it can be transformed in high yields and very good E/Z-diastereoselectivity to tert-butyl (E/Z)-2-alkoxycyclopropanecarboxylates 4. This two step synthesis of 4 represents a simple and safe alternative to existing methods using diazo compounds.

Porous polymer packings from vinyl ether derivatives for reversed-phase liquid chromatography

Spherical, porous-polymer particles for column packing in high-performance liquid chromatography were prepared by suspension copolymerization of alkylvinyl ether with triethyleneglycol divinyl ether. The hydrophobicity of the packings was easily adjusted by changing the monomer ratio. The packings showed the usual reversed-phase liquid chromatographic properties, but did not sho abnormal retention, tailing and broadening of peaks and irreversible adsorption of ionic and aromatic substances, owing to the lack of ionic or aromatic groups. In addition, the packings were stable in alkaline solutions because of the relative alkali stability of C−O−C bonds as compared with CO−O and Si−O−C bonds in conventional packings.

Optically active polymers containing side‐chain photochromic moieties. Synthesis and chiroptical properties of copolymers of trans‐N(4‐azobenzene)‐maleimide with (−)‐menthyl vinyl ether and (+)(S)‐2‐methylbutyl vinyl ether

AbstractThe copolymers of trans‐N(4‐azobenzene)‐maleimide (ABM) with optically active alkyl vinyl ethers, such as (−)‐menthyl vinyl ether (MtVE) and (+)S‐2‐methylbutyl vinyl ether (MBVE), have been prepared either by direct copolymerization or by functionalization with trans‐4‐amino‐azobenzene of the corresponding alternating copolymers of maleic anhydride with MtVE and MBVE. The chiroptical properties of the above copolymers have been studied by CD measurements. The induced optical activity on the side‐chain trans‐azobenzene moieties is discussed in terms of different conformational rigidity of the macromolecules.

Molecular engineering of liquid-crystal polymers by living polymerization. 14. Synthesis and characterization of binary copolymers of .omega.-[(4-cyano-4'-biphenyl)oxy]alkyl vinyl ethers containing undecanyl and hexyl, pentyl and propyl, and undecanyl and propyl pairs of alkyl groups

Abstract : Copolymerization represents the simplest synthetic technique which can be used to tailor make phase transitions of both main chain and side chain liquid crystalline polymers. Indeed, copolymerization was frequently employed to manipulate the phase transitions of side chain liquid crystalline polymers. However, most of the results reported in the literature can be considered only in a qualitative way, since there are only very few cases in which information about both copolymer composition and molecular weight are available. A general classification of side chain liquid crystalline copolymers was recently discussed in a review article. There are two main classes of side chain liquid crystalline copolymers. The first one refers to copolymers containing pairs of structural units with and without mesogenic units. This class of copolymers was extensively investigated. The second class refers to copolymers based on pairs of structural units containing mesogenic units in each one.

Synthesis of new, functionalized poly(butyl vinyl ether) oligomers and novel copolymers containing these materials

AbstractThis paper reports the synthesis and characterization of new, functionalized poly(alkyl vinyl ether) oligomers, and block copolymers containing poly(alkyl vinyl ether) and poly(methyl methacrylate). Using the HI/ZnI2 initiating system in nonpolar solvents (hexane, toluene) at −20°C, both monofunctional and difunctional poly(alkyl vinyl ether) oligomers of predicted molecular weights precisely terminated with aldehyde, primary hydroxyl and ester endgroups have been prepared. Novel diblock copolymers comprised of poly(methyl methacrylate) and poly(butyl vinyl ether) have also been synthesized using a combination of living cationic and living group transfer polymerization.

Molecular Engineering of Liquid Crystal Polymers by Living Polymerization. VIII. Influence of Molecular Weight on the Phase Behavior of Poly {ω-[(4-Cyano-4′-biphenyl)-oxy]alkyl Vinyl Ether}s with Ethyl, Propyl, and Butyl Alkyl Groups

Abstract The synthesis and living cationic polymerization of 2-[4-cyano-4′-biphenyl)oxy]ethyl vinyl ether (6–2), 3-[4-cyano-4′-biphenyl)oxy]-propyl vinyl ether (6-3), and 4-[4-cyano-4′-biphenyl)oxy]butyl vinyl ether (6-4) are described. The mesomorphic behaviors of poly(6–2), poly(6-3), and poly(6-4) with different degrees of polymerization and narrow molecular weight distributions were compared to those of 6–2, 6–3, and 6–4 and of 2-[(4-cyano-4′-biphenyl)oxy]ethyl ethyl ether (8–2), 3-[(4-cyano-4′-biphenyl)oxy]propyl ethyl ether (8–3), and 4-[4-cyano-4′-biphenyl)oxy]butyl ethyl ether (8–4) which are model compounds of the monomeric structural units of poly(6–2), poly(6–3), and poly(6–4). In the first heating scan, all three polymers exhibit an x (unidentified) mesophase which overlaps the glass transition temperature, and an enantiotropic nematic mesophase. In the second and subsequent heating and cooling scans, poly(6–3) and poly(6–4) display only the enantiotropic nematic mesophase. Both in the first and subsequent scans, only poly(6–2) with degrees of polymerization lower than 4 exhibits an enantiotropic nematic mesophase.

Molecular engineering of liquid crystalline polymers by living polymerization. 10. Influence of molecular weight on the phase transitions of poly{ι-[(4-cyano-4'-biphenylyl)oxy]alkyl vinyl ether}s with nonyl and decanyl alkyl groups

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMolecular engineering of liquid crystalline polymers by living polymerization. 10. Influence of molecular weight on the phase transitions of poly{ι-[(4-cyano-4'-biphenylyl)oxy]alkyl vinyl ether}s with nonyl and decanyl alkyl groupsVirgil Percec and Myongsoo LeeCite this: Macromolecules 1991, 24, 10, 2780–2788Publication Date (Print):May 1, 1991Publication History Published online1 May 2002Published inissue 1 May 1991https://doi.org/10.1021/ma00010a022RIGHTS & PERMISSIONSArticle Views227Altmetric-Citations73LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (868 KB) Get e-Alerts Get e-Alerts

Polyoxazoline containing copolymers useful as emulsifiers for polymer blends

AbstractThe preparation of new block and graft copolymers containing poly (2‐alkyloxazoline)s using macroinitiator methods have been investigated. Hydroxy terminated poly(2‐alkyloxazoline) oligomers can be synthesized using alkyl iodide initiators and potassium hydroxide as the terminating reagent. Polymerizations of ϵ‐caprolactone using monofunctional poly(2‐alkyloxazoline)s as macroinitiators and Sn(oct)2 as the catalyst yield diblock copolymers of poly(2‐alkyloxazoline‐b‐ϵ‐caprolactone) with controlled molecular weights. Graft copolymers have also been prepared by first generating a poly(alkyl vinyl ether) backbone. Copolymerization of a low molar percentage of 2‐chloroethyl vinyl ether with alkyl vinyl ethers was performed using a heterogeneous cationic catalyst to yield high molecular weight random copolymers with pendent ethyl chloride groups interspersed along the chain. This pendent chlorine group, together with NaI, was used as the initiation system for 2‐alkyloxazoline grafts. Characterization of the resultant copolymers by gel permeation chromatography, intrinsic viscosity, DSC, solution and solid state 1H and 13C NMR is discussed. These materials are being evaluated as emulsifiers for polymer blends containing aliphatic polyamides as one component.

Calculation of the torsional angles in alkyl vinyl ethers from the direct13C-1H spin-spin interaction constants

It is shown that the differences in the direct13C-1H SSIC of the Cβ atom of the vinyl groups in alkyl vinyl ethers depend on the value of the torsional angle about the Cα bond. This dependence is used to make quantitative estimates of the torsional angles in alkyl vinyl ethers with alkyl substituents ranging from CH3 to t-C4H9

Preparation of ester terminated poly(alkyl vinyl ether) oligomers and block copolymers using a combination of living cationic and group transfer polymerization

This paper reports the synthesis and characterization of new, functionalized poly(alkyl vinyl ether) oligomers, and block copolymers containing poly(alkyl vinyl ether) and poly(methyl methacrylate). Using the HI/ZnI2 initiating system in nonpolar solvents (hexane, toluene) at -15 °C, both monofunctional and difunctional poly(alkyl vinyl ether) oligomers of predicted molecular weights precisely terminated with ester end groups have been prepared. Novel diblock copolymers comprised of poly(methyl methacrylate) and poly(alkyl vinyl ether) have also been synthesized using a combination of living cationic and living group transfer polymerization (GTP) techniques.