Styrene-n-butyl acrylate copolymers

The degree of structure, i.e., number average sequence lengths, also composition were determined for styrene-n-butyl acrylate copolymers and compared to those obtained for homogenous, i.e., non-structured (random), copolymers. 

Wang and co-workers [90] showed that pyrolysis - gas chromatography of styrene- butyl acrylate can be used to obtain the number average sequence length which can be further used to calculate the percentage of monomer in these copolymers. 

In a procedure described by Sharp and Patterson [91] the acrylic acid and methacrylic acid groups in acrylic copolymers are first propylated using dimethyl formamide dipropyl acetal then this product pyrolysed according to the following scheme  

The resulting pyrolysis products (propylacrylate and methacrylate) are separated on a gas chromatograph and analysed by mass spectrometry. 

By this procedure, copolymerised acrylic or methacrylic acid has been identified in terpolymers with (a) butyl acrylate and styrene (b) methyl methacrylate and ethyl 

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Al-Ghamdi GH, Sudol ED, Dimonie VL, et al. (2006) Encapsulation of titanium dioxide in styrene/n-butyl acrylate copolymer by miniemulsion polymerization. J Appl Polym Sd 101 3479-3486... 

Recently, a series of styrene-n-butyl acrylate copolymer latexes were prepared by conventional or miniemulsion polymerization techniques which incorporated TMI and/or methacrylic acid (MAA), and the interfacial crosslinking behaviour of films derived firom these latexes was investigated [33]. It was shown that crosslinking was dramatically enhanced in the presence of MAA. However, films prepared with TMI also crosslinked in the presence of atmospheric moisture with time at room temperature. This work also demonstrated the stability of... 

Structure Determination of Styrene-n-Butyl Acrylate Copolymers... 

Cheng-Yu Wang et af applied pyrolysis gas chromatography to the determination of the structure of styrene-n-butyl acrylate copolymers. The number average sequence length which reflects monomer arrangement was calculated using formulae that incorporate pure trimer peak intensities and hybrid trimer peak intensities. 

Many investigators have studied polymer surfaces for years [74,75] and have been successful in determining combinations of two or more valence states [76,77] by the mathematical process of deconvoluting the peak assignments [78]. It was only recently that latexes were examined by ESCA. Davies et al. [79] prepared a series of homopolymers of poly(methyl methacrylate) (PMMA) and poly(butyl methacrylate) (PBMA), and also poly[(methyl methacrylate)-co-(butyl methacrylate)] (PMMA-PBMA), by surfactant-free emulsion polymerization. It was found that the surface of the latex film was rich in PMMA, which may possibly be explained by the reactivity ratios for the MMA/BMA system (ri = 0.52 and rj = 2.11) [80], Recently, Arora et al. carried out angle-dependent ESCA studies on a series of films prepared from core-shell ionomeric latexes (with a polystyrene core and a styrene/n-butyl acrylate/ methacrylic acid copolymer shell) to determine the distribution of carboxyl groups in the films [81,82]. 

Ruthenium alkoxycarbene complexes synthesised so far were inefficient for the controlled ATRP of styrene and n-butyl acrylate, so that the strategy developed above could not be extended to the synthesis of controlled poly(norbomene-g-styrene) and poly(norbomene-g-n-butyl acrylate) copolymers(Scheme 14). The controlled synthesis of poly(norbomene-g-styrene) could however be achieved in a two-step approach using the poly(NB-co-NB-Br) macroinitiator in conjunction with typical catalyst systems for ATRP, such as NiBr2(PPh3)2. 

Strategies for controlling the copolymer composition and MWD of latices based on linear and non-linear copolymers, such as styrene/butyl acrylate copolymers and methyl methacrylate/n-butyl acrylate copolymers, are described. These strategies involve on-line procedures based on calorimetric measurements and open-loop processes employing a mathematical model for determining the trajectories of the manipulated variables, such as monomer feed flow rates and chain transfer agent. 35 refs. (3rd lUPAC-Sponsored International Symposium on Free-Radical Polymerization Kinetics and Mechanism, II Ciocco (Lucca), Tuscany, Italy, 3rd-9th June, 2001)... 

METHOD 95 - DETERMINATION OF STYRENE AND METHACRYLATE UNITS IN STYRENE-METHYL MET ACRYLATE AND STYRENE N-BUTYL METHACRYLATE COPOLYMERS. PYROLYSIS - GAS CHROMATOGRAPHY... 

GugUotta et al. [23] developed a new approach to estimate the monomer conversion and copolymer composition in semibatch emulsion copolymerization systems based on reaction calorimetric measurements. The vaUdity of this technique was confirmed by the semibatch emulsion copolymerizations of both the styrene-n-butyl acrylate and vinyl acetate-n-butyl acrylate. 

ITP from a multifunctional macrotransfer agent was also used to prepare poly(e-caprolactone) (PCL)-based graft copolymers. Thus, FTP of styrene, n-butyl acrylate, and N,N-dimethylacrylamide was performed in the presence of poly(e-caprolaaone-co-a-iodo-e-caprolactone) to obtain PCL- -PS, PCL- -PnBuA and PCL-g-PDMA, respectively. ... 

Figure 4.4 Experimentally determined monomer fractions in latex particles as a function of the monomer fraction in the monomer droplets. Q methyl acrylate-vinyl acetate in a poly-(MA-VAc) copolymer latex. A methyl acrylate- styrene, n-butyl acrylate-styrene, methyl acrylate-n-butyl acrylate, methyl acrylate-methyl methacrylate and methyl methacrylate-styrene on several (co)polymer seeds. The solid line represents the prediction by Equation 4.13 (Verdurmen-Noel, 1994).

In 1975 Wacker-Chemie introduced silicones under the name of m-polymers. These are also room temperature curing liquid polymers which give rubbery materials on cross-linking and are available both as one- and two-component systems. Their particular feature is that they contain dispersions of copolymers such as those of styrene and n-butyl acrylate in the shape of rods or rice grains in the fluid silicone polymer. A small amount of the organic copolymer is also grafted onto the silicone backbone. 

ARGET ATRP has been successfully applied for polymerization of methyl methacrylate, ft-butyl acrylate and styrene in the presence of Sn(EH)2 (10 mol% vs. alkyl halide initiator or 0.07 mol% vs. monomer) [164,165]. For all monomers, polymerizations were well controlled using between 10 and 50 ppm of copper complexes with highly active TPMA and Me6TREN ligands. ARGET ATRP has also been utilized in the synthesis of block copolymers (poly(n-butyl acrylate)— -polystyrene and polystyrene-Z -poly(n-butyl acrylate) [164,165] and grafting... 

Figure 2.3 Relationship between polydispersity of the resulting random copolymers and mole percent of styrene in the feed mixture for the copolymerization of (i) styrene and n-butyl acrylate (Ob and (ii) styrene and methyl methacrylate ( ) mediated by 14...

Bauer et al. describe the use of a noncontact probe coupled by fiber optics to an FT-Raman system to measure the percentage of dry extractibles and styrene monomer in a styrene/butadiene latex emulsion polymerization reaction using PLS models [201]. Elizalde et al. have examined the use of Raman spectroscopy to monitor the emulsion polymerization of n-butyl acrylate with methyl methacrylate under starved, or low monomer [202], and with high soUds-content [203] conditions. In both cases, models could be built to predict multiple properties, including solids content, residual monomer, and cumulative copolymer composition. Another study compared reaction calorimetry and Raman spectroscopy for monitoring n-butyl acrylate/methyl methacrylate and for vinyl acetate/butyl acrylate, under conditions of normal and instantaneous conversion [204], Both techniques performed well for normal conversion conditions and for overall conversion estimate, but Raman spectroscopy was better at estimating free monomer concentration and instantaneous conversion rate. However, the authors also point out that in certain situations, alternative techniques such as calorimetry can be cheaper, faster, and often easier to maintain accurate models for than Raman spectroscopy, hi a subsequent article, Elizalde et al. found that updating calibration models after... 

ASA structural latexes have been synthesized in a two stage seeded emulsion polymerization. In the first stage, partially crosslinked poly(n-butyl acrylate) and poly( -butyl acrylate-sfaf-2-ethylhexyl acrylate) rubber cores are synthesized. In the second stage, a hard styrene acrylonitrile copolymer (SAN) shell is grafted onto the rubber seeds (16). 

Styrene copolymers of methyl, ethyl, and n-butyl acrylates and methacrylates were also separated according to their compositions (8) (Figure 3). Part of poly (styrene-ethyl methacrylate) P(S-EMA) copol-... 

According to literary data, the following mixtures of aromatic/aliphatic-aromatic hydrocarbons were separated toluene/ n-hexane, toluene/n-heptane, toluene/n-octane, toluene/f-octane, benzene/w-hexane, benzene/w-heptane, benzene/toluene, and styrene/ethylbenzene [10,82,83,109-129]. As membrane media, various polymers were used polyetherurethane, poly-esterurethane, polyetherimide, sulfonyl-containing polyimide, ionicaUy cross-linked copolymers of methyl, ethyl, n-butyl acrylate with acrilic acid. For example, when a composite polyetherimide-based membrane was used to separate a toluene (50 wt%)/n-octane mixture, the flux Q of 10 kg pm/m h and the separation factor of 70 were achieved [121]. When a composite mebrane based on sulfonyl-containing polyimide was used to separate a toluene (1 wt%)/ -octane mixture, the flux 2 of 1.1 kg pm/m h and the separation factor of 155 were achieved [10]. When a composite membrane based on ionically cross-linked copolymers of methyl, ethyl, w-butyl acrylate with acrilic acid was used to separate toluene (50 wt%)//-octane mixture, the flux Q of 20-1000 kg pm/m h and the separation factor of 2.5-13 were achieved [126,127]. 

The paint studied is a typical automotive thermosetting enamel which consists of an epoxy functional acrylic copolymer and butylated melamine crosslinking agent. The acrylic copolymer is composed of methyl methacrylate, n-butyl methacrylate, n-butyl acrylate, styrene, acrylonitrile, 2-ethyl hexyl acrylate and 2-hydroxyethyl methacrylate. Carbon black was used as the pigment. 

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