Reactive polymers. VIII. Reaction of the epoxide groups of the copolymer glycidyl methacrylate – ethylenedimethacrylate with aliphatic amino compounds

The reaction of macroporous copolymers glycidyl methacrylate – ethylenedimethacrylate with ammonia, primary and secondary amines, diamines and hydroxyalkyl amines leading to products with wide applicability was investigated. The reaction can be carried out without or with solvent, water being quite sufficient as the latter. The effects of amine concentration, substituents, temperature and type of the solvent on the reaction course were examined. The reaction product with dimethyl amine and 2-hydroxyethyl amine was alkylated consecutively, and a strongly basic anion exchanger of second type was obtained.     

Reactive polymers,XXIX. The effect of components on the rate of polymerization in model mixtures containing glycidylmethacrylate and ethylenedimethacrylate

The effect of the concentration of crosslinking agent, of the amount and composition of inert components and of the concentration of initiator on the process of radical copolymerization of glycidylmethacrylate with ethylenedimethacrylate modelling the situation arising in suspension polymerization has been studied. It was found, that the rate of polymerization decreases with increasing concentration of the crosslinking agent in the mixture, which also brings about extension of the time after which the reaction mixture becomes turbid. Causes underlying these phenomena are discussed.     

Reactive polymers,XXVII. Kinetics of chemical reactions of metal ions with functional groups of glycidyl methacrylate — ethylenedimethacrylate copolymers modified by ethylenediamine

The conditions were followed which influence the rate of uptake of Cu(II) and Ag(I) ions by a copolymer of glycidyl methacrylate with ethylene dimethacrylate modified by ethylenediamine. In addition to the particle size (0.1–1 mm) of the chelating resin, the concentration of cations in solution affects substantially the rate of sorption. It follows from the calculated rate of diffusion and from the rate constants of the chemical reaction that the reaction kinetics is decisive for particles below 0.1 mm, whereas with increasing particle size the inner diffusion begins to play a more important role and becomes finally the rate-determining mechanism. The obtained results are supported by observations of morphology.     

Reactive polymers. XXVI. Sorption properties of the glycidylmethacrylate-ethylenedimethacrylate copolymer modified with ammonia

Sorption properties of the glycidylmethacrylate-ethylenedimethacrylate copolymer with the ? OH and ? NH₂ groups were characterized by using the static and dynamical procedure. Hg(II) was found to be sorbed selectively from the acetate buffer. Using sorption and desorption isoplanes determined in the measurements, conditions of the sorption of Hg(II) and its separation from an excess of some metal ions (Cu(II), Pb(II), Cd(II), Co(II), Zn(II), Ca(II), Mg(II)) were determined.     

Polythiocarbamate polymers II.—Optimum conditions for synthesis

Polythiocarbamate polymers have been prepared from a prepolymer containing terminal isocyanate groups, obtained from reaction of a low molecular weight thiol-terminated polymer with a diisocyanate. The prepolymer was chain extended and crosslinked with diols. and triols. Optimum conditions for prepolymer formation were established. Void formation in prepolymer is avoided by use of antioxidants but is difficult to prevent in the crosslinked material. Isocyanate appeared to be consumed in a reaction other than directly with thiol, and a water-forming oxidation may be involved. A crosslinking reaction involving the thiocarbamate hydrogen and isocyanate appears to be favoured, contrary to results with carbamates. The nature of an isocyanate and catalyst complex is discussed.     

Reactive polymers. XII. Bead macroporous methacrylate terpolymers containing aldehyde groups

Bead macroporous terpolymers of methacrylaldehyde with methyl methacrylate and ethylene dimethacrylate were prepared. Preparation conditions (composition of the monomer mixture, of the inert components, concentration of the initiator and of the suspension stabilizer, and the rate of stirring) were discussed with respect to the properties of the terpolymers (porosity and concentration of reactive aldehyde groups). Concentration of reactive groups in the polymer was controlled by adding a third monomer. The analytically determined differences in the concentration of the reactive groups in the batch and in the polymer were interpreted (a) by the inaccessibility of the groups within the polymer bulk (for polymers with 30–50 mol-% of crosslinking agent), (b) by the presence of tetrahydropyran rings or acetate bonds between the chains, and (c) by the formation of extractable soluble polymers or copolymers, or by not reacting of parts of the monomers (observed predominantly with low-crosslinked polymers containing 10 mol-% of crosslinking agent).     

Hydrolysis of poly(acrylamide)–starch graft copolymer

Poly(acrylamide)–starch graft copolymer was treated independently with sodium hydroxide and different acid solutions. The different acids include phosphoric, hydrochloric, and sulphuric acid. The treatment was carried out under a variety of conditions including sodium hydroxide concentration, time, and duration of hydrolysis as well as type of acid used. The extent of hydrolysis was assessed by estimating amide and carboxyl content as well as the acrylate and starch content before and after treatment. It was found that the increment in carboxyl content is equal to the decrement in amide on using sodium hydroxide concentration up to 1N, while using higher concentration than 1N leads to a difference in formed carboxyl and decreased amide groups. The magnitude of this difference depends on sodium hydroxide concentration as well as temperature and duration of hydrolysis. The maximum value of carboxyl content obtained was 593 meq/100 g sample. The acidic treatment of the starch copolymer does not affect the conversion of amide groups to carboxyl groups, and the sole effect was hydrolysis of starch component of the copolymer. Evaluation of the alkali-treated copolymer as cation exchanger was carried out. The absorption efficiency % of different cations depends on the associated anions and follow the order: Cu²⁺ > Zn²⁺ > Co²⁺ > Mg²⁺. © 1995 John Wiley & Sons, Inc.     

Reactive polymers. XX. The preparation of a carrier with aldehyde groups by oxidation of a macroporous glycidyl methacrylate-ethylenedimethacrylate copolymer with periodic acid

The oxidation of a macroporous glycidyl methacrylate-ethylenedimethacrylate copolymer and of a polymer formed by its hydrolysis was investigated at temperatures ranging from 5 to 80°C with various concentrations of periodic acid. The reaction yields (formylmethyl)-methacrylate units bearing free aldehyde groups capable of further reactions. The results allowed to estimate the activation energy of the reaction (60 and 27.5 kJ mol^-1) and to discuss its mechanism. The oxidation of the epoxide group seems to proceed in two steps with vicinal glycol as the intermediate product.     

Reactive polymers. 60. glycidyl methacrylate-styrene-ethylene dimethacrylate terpolymers modified with strong-acid groups

Glycidyl methacrylate-styrene-ethylene glycol dimethacrylate (GMA-ST-EDMA) terpolymers were prepared by suspension radical polymerization. The polymer is enriched in styrene during the polymerization, and this can be explained by kinetic and thermodynamic factors operating simultaneously. The terpolymers were used in the preparation of strong-acid ion exchangers. Special attention was paid to the stability of ion exchange derivatives under the conditions of ion exchange. The GMA-EDMA copolymer, which according to its IR spectra contained sulfonate groups, was the most stable: its exchange capacity did not decrease even after one hundred exchange cycles. Modified GMA-ST-EDMA terpolymers undergo an autocatalytic hydrolysis of the polymeric matrix, which gradually dissolves.     

Reactive polymers. XXI. Preparation and characterization of crosslinked polymers with functional aldehyde groups and their reactivity

Crosslinking polymerization leading to poly(styrene-co-divinylbenzene-co-methacrolein) and poly(divinylbenzene-co-methacrolein) was studied together with the reactivity of the functional aldehyde groups. The surface characteristics of prepared polymers and their reactivity depend on the composition of the inert phase used in the suspension polymerization.     

Stress-relaxation crazing of polymers — an energy criterion

One of the most important signs of failure, easily observable in transparent and translucent polymers, is the appearance of visible crazes. The observation of first crazes is relatively simple in uniaxial long-term experiments (such as creep and stress-relaxation). An energy-related crazing criterion has allowed good predictions of the appearance of first visible crazes under uniaxial creep loading conditions. The results have shown that in spite of the different applied stresses and different corresponding crazing times, the specific dissipated energy at crazing was the same. The objective of the present work was to investigate if this criterion, based on the constancy of the specific dissipated energy, is valid also for uniaxial stress-relaxation. The good agreement between theoretical predictions and experimental results confirms this assumption.     

Reactive microgels—polymers intermediate in size between single molecules and particles

Reactive microgels are considered as soluble intramolecular cross-linked macromolecules, with sizes comparable to linear or branched macromolecules and reactive groups at their surface or interior. This article is the written version of a Macrolux 1988 lecture. It presents the history and some more important results and relationship of synthesis, characterization and properties of this group of polymers and refers briefly to application.     

Telechelic polymers — precursors to high solids coatings

Coating industry concerns for energy and environmental cost in formulation suggest high solids coatings as an alternative. The use of 100% active coatings, wherein the polymeric binder precursor has functional groups on the chain ends, is rationalized. However, the use of liquid ‘telechelic’ polymer requires the knowledge of syntheses for understanding of fluid properties, cures and physical properties after cure. Synthesis techniques control these end results through their influence on type and amount of functionality, chain configurations and by-products.

As the techniques for making carboxy- or hydroxy-telechelic polyesters or hydroxy-telechelic polyethers have been the object of considerable study and review, this review deals with syntheses based upon addition polymers. The synthesis methods' impact on functionality (type and amount) is emphasized. Fluid property expectations are also noted, and analysis techniques summarized. Currently commercial polymers are cited with notation as to recommended cure and uses. A Summary of cure studies, mostly with emphasis on the applications (e.g. rocket propellant binders, sealants, coatings and so on) is also included.

The conclusions are that current problems with rheology, cure rates and chemistry, and final coating properties may be overcome by appropriate research. These efforts are already under way in some segments of the industry, and high solids coatings or 100% active coatings will be a growing factor in the market place. The prime objective of this review is to gather some of the pertinent information on synthesis, properties and application of the telechelic polymers as a guide to the research on high solids coatings.     

Anionic alternating copolymerization of epoxide and 3,4‐dihydrocoumarin and its application to networked polymers

3,4‐Dihydrocoumarin (DHCM) is an aromatic six‐membered lactone, which does not undergo anionic homopolymerization. However, it does undergo copolymerization with an epoxide. The striking feature of this copolymerization is its 1:1 alternating nature, which allows for the formation of polyesters. In this mini‐review, we describe the copolymerization behavior, the polymer structure and the advantages that can be achieved by addition of DHCM to the epoxy‐imidazole curing system. Another focus is our development of DHCM analogues, which bring the advantages of DHCM to their applications as comonomers for the curing system. Copyright © 2009 Society of Chemical Industry     

Novel functional polymers: Poly(dimethylsiloxane)–polyamide multiblock copolymer. III. Synthesis and surface properties of disiloxane–aromatic polyamide multiblock copolymer

Disiloxane–aromatic polyamide(aramid) multiblock copolymers(2SiPASs) were synthesized using 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane(BATS) as an analog of aramidsilicone resin consisting of aromatic polyamide and poly(dimethylsiloxane) (PDMS). 2SiPASs afford a transparent and toughened plastic film. The surface properties of 2SiPAS were investigated by X-ray photoelectron spectroscopy (xps) and static contact angle measurement. The results of surface analysis suggested that BATS content of the 2SiPAS surface increased with increasing BATS content in bulk. The interaction between the platelets and the 2SiPAS surface was found to be very weak when the BATS content reached 26 wt % in bulk. © 1996 John Wiley & Sons, Inc.     

Reactive Dyes and Resin-treated Wool — Keys to the Attainment of Superwash Standards

The importance of control in the application of the water-soluble polymer, Hercosett 57, to prechlorin-ated wool tops and garments, is stressed with special reference to its effect on washability and subsequent dyeing operations. Reactive dyes play a vital role in achieving adequate colour fastness to meet machine-washable specifications and this paper pays special attention to problems of wet fastness encountered with full-depth dyeings produced with these dyes. In order to overcome these problems, both the dyeing operation and the after-treatment stage have been closely studied. A novel after-treatment is proposed as being more effective than the usual dilute ammonia method. Both high-temperature dyeing and low-temperature dyeing are discussed, the former method showing advantages in the case of full-depth dyeings and the latter in the case of pale-depth dyeings.     

Heterogeneous network polymers. IV. Dynamic mechanical properties—composition—phase structure relationships

Heterogeneous network polymers were prepared from poly(D -glutamic acid) (PGA) and poly(oxyethylene glycol) (PEG). The content of PGA was systematically varied: 30%, 40%, 50%, 60%, 65%, and 70% by weight. The molecular weights of the crosslinking PEG were 300, 600, 900, and 1800. The plots of the dynamic mechanical tan δ peak temperatures, the PGA interhelical distances (x-rays) and the densities against PGA contents showed a distinct break between 50% and 60%. The photographs under polarizing microscope also indicated an occurrence of phase inversion in the above content region. PGA containing small amounts of PEG and PEG containing small amounts of PGA were found to constitute the continuous phases, respectively, above and below the phase inversion region, while a well-mixed phase is always the dispersed phase. The glass transition was ascribed to the micro-Brownian motions of PGA, PEG, and PEG above and below the phase inversion region, respectively.     

Publication Sponsored by the Society's Colour Measurement Committee — XIV The Impact of Modern Lighting on the Dyer

Until recently, the two desirable characteristics of high lamp efficacy and good colour rendering were mutually exclusive in fluorescent lamps but in 1971 calculations were made which showed that they could co-exist if the emitted light approached a 3-line spectral power distribution (SPD), ideally the emission bands being at 450, 540 and 610 nm. The discovery of new phosphors has made such lamps a practical possibility and two manufacturers have marketed lamps whose SPDs lie between the continuous SPD of conventional lamps and the 3-line ideal. Such lamps have been found to render many objects more colourful than any conventional lamps and thus more acceptable to the average observer. This combination of desirable characteristics suggests that such lamps may become the most common form of artificial lighting, especially in view of the need to conserve fossil fuels. Tire installation of one of these lamps in a large department store, however, caused some serious problems with textiles which were metameric matches. These may be more serious with sources whose SPDs are closer to the 3-line ideal. The same problems will also occur with nontextile materials, e.g. ceramics and plastics, which match under various conventional sources. These developments in lighting may make extensive re-matching necessary.