Grafting styrene//-butyl acrylate

Abele, S., Gauthier, C., Graillat, C. and Guyot, A. (2000) Films from styrene-butyl acrylate lattices using maleic or succinic surfactants mechanical properties, water rebound and grafting of the surfactants. Polymer, 41, 1147-55. 

Increased toughness and colourability over conventional ASA-PC blends can be attained by using a two-stage grafted n-butyl acrylate core [70]. In the first grafting step pure styrene is added followed by a styrene-acrylonitrile... 

Encapsulation of nanostructured 3-trimethyloxysilyl propyl methacrylate (MPS)-grafted silica beads was performed by dispersion polymerisation of styrene, butyl acrylate and butyl methacrylate in a mixture of ethanol... 

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. 

ATRP and grafting from methods led to the synthesis of poly(styrene-g-tert-butyl acrylate)-fr-poly(ethylene-co-butylene)-fr-poly(styrene-g-ferf-butyl acrylate) block-graft copolymer [203]. ATRP initiating sites were produced along the PS blocks by chloromethylation as shown in Scheme 112. These sites then served to polymerize the ferf-butyl acrylate. The poly(ferf-butyl acrylate) grafts were hydrolyzed to result in the corresponding poly(acrylic... 

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 14.9 Effect of various impact modifiers (25wt%) on the notched Izod impact strength of recycled PET (as moulded and annealed at 150°C for 16 h) E-GMA, glycidyl-methacrylate-functionalized ethylene copolymer E-EA-GMA, ethylene-ethyl acrylate-glycidyl methacrylate (72/20/8) terpolymer E-EA, ethylene-ethyl acrylate EPR, ethylene propylene rubber MA-GPR, maleic anhydride grafted ethylene propylene rubber MBS, poly(methyl methacrylate)-g-poly(butadiene/styrene) BuA-C/S, poly(butyl acrylate-g-poly(methyl methacrylate) core/shell rubber. Data taken from Akkapeddi etal. [26]...

In this review, synthesis of block copolymer brushes will be Hmited to the grafting-from method. Hussemann and coworkers [35] were one of the first groups to report copolymer brushes. They prepared the brushes on siUcate substrates using surface-initiated TEMPO-mediated radical polymerization. However, the copolymer brushes were not diblock copolymer brushes in a strict definition. The first block was PS, while the second block was a 1 1 random copolymer of styrene/MMA. Another early report was that of Maty-jaszewski and coworkers [36] who reported the synthesis of poly(styrene-h-ferf-butyl acrylate) brushes by atom transfer radical polymerization (ATRP). 

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). 

On the other hand, chemicals might be chosen as agents for generation of active centers in the polymeric backbone and grafting of monomer in the vapor phase. Ammonium persulfate and styrene (189), acrylic acid (190), butyl acrylate (191), potassium persulfate and n-butyl maleate or 2-ethyl hexyl acrylate (55,134) and ammonium ceric nitrate and methacrylic add (192) are examples of this method. Benzoyl peroxide deposited on polycaprolactam fibers initiates the grafting of styrene in vapor phase (193). 

For example polymethyl acrylate was treated with phosphorus penta-chloride to form copolymers containing 26.6 and 37.8% acid chloride units these copolymers, by treatment with tert-butyl hydroperoxide, yield 4.9 to 6% perester containing polymers which were used for grafting styrene, vinyl acetate, acrylonitrile (177). 

The macromonomers thus obtained exhibit molecular weights as low as 1000. They were copolymerized with monomers such as styrene and butyl acrylate whereby graft copolymers with poly(vinyl chloride) grafts were obtained. 

Returning to Vollmert s patent (18), we apply the more complete spectrum of operations to his example 1. In this case butyl acrylate and acrylic acid are dissolved in acetone with azoisobutyronitrile (initiator) and dodecyl mercaptan (chain transfer agent), polymerized, and the acetone is evaporated to form polymer 1. Separately, styrene and 1,4-butanediol monoacrylate are bead polymerized with benzoyl peroxide to form polymer 2. Polymers 1 and 2 are mechanically blended with the simultaneous addition of 1,4-butanediol followed by heating to promote grafting and crosslinking. These steps can be represented in some detail by ... 

Material. Optically clear films (about 5 mils thick) of three SA (saturated acrylic) plastics (3) that contained 25, 33, and 50% of an acrylic graft rubber (referred to as SA-1, SA-2, and SA-3) were compression molded. The acrylic graft rubber latices were latex blended with a resin latex composed primarily of methyl methacrylate, and the blend was coagulated. The compositions of these three polymers are as follows SA-1, 79/17/4 wt %—methyl methacrylate/butyl acrylate/styrene SA-2, 72/23/5 wt %—methyl methacrylate/butyl acrylate/styrene SA-3, 59/34/7 wt %—methyl methacrylate/butyl acrylate/styrene. All three graft rubbers contained low levels of a crosslinking comonomer (less than 1.0 wt %). 

Figure 19.13 shows the dynamic mechanical properties of such a blend of sPS with a mixture of Kraton G 1651 (15 %) and microsuspension rubber particles (20%) consisting of 60% butyl acrylate (BA) core grafted with 40% styrene shell (S//BA). The glass transition temperatures of the Kraton (-60 °C) and the butyl acrylate (-45 °C) phases can be easily distinguished from one another. The TEM image of such a product after deformation is shown in Figure 19.14. The annealed specimen is shown since the two rubber types are better discernible than in the nonannealed sample. As expected, crazing and voiding in the rubber particles dominate. The product had the following notched impact strengths (ISO 179/eA) injection moulded (80 °C mould temperature) 6.3, injection moulded (140 °C) 4.0 and annealed 3.7kJ/m2.

Blends consisting of crosslinked butyl acrylate particles (core) grafted with styrene (shell) have been reported in the literature. The particles were prepared using microsuspension [8] (0.5-2.0 pm) or emulsion (particle diameter 0.12 xm) polymerization processes [9]. 

The TEM images (Figure 25.7) show the rubber particles (a) MSP 1, (b) MSP2, and (c) MSP 3 mixed into the S/DPE matrix containing 15 % DPE. Figure 25.8 shows the morphology of MSP 1 in S/DPE(30). The blends were injection moulded to dumbbell test pieces. In all cases the grafted rubber concentration was 36 wt%. These rubber particles consist of 40 % styrene as the outer shell, for compatibility with the S/DPE copolymer, and 60 % crosslinked butyl acrylate rubber as the... 

The composition of the PAA-g-PS graft copolymer reaction product and its purification, especially as far as the removal of unreacted PS-MA macromonomer by silica column chromatography is concerned, and the successful selective cleavage of the ferf-butyl ester under acidic conditions to render the graft copolyelectrolyte PAA-g-PS were analyzed by XH NMR spectroscopy and SEC. Figure 8a shows the SEC curves of the polystyrene macromonomer (PS-MA), the crude poly (ferf-butyl acrylate-gra/f-styrene) (PTBA-g-PS) and the PTBA-g-PS the polymethylacrylate (PMA) originates from esterification of the poly (acrylic acid) (PAA) obtained after complete saponification of the graft copolymer and represents the backbone. The XH NMR spectra of PSMA, PTBA-g-PS and of the final reaction product PAA-g-PS are shown in Fig. 8b. 

Fig. 8 (a) SEC curves of the PS macromonomer (PS-MA curve 1), the crude (curve 2) and the purified (curve 3) poly( ter t-butyl acrylate-gra/f-styrene) (PTBA-g-PS), and the esterified polymethylacrylate (PMA curve 4) backbone, (b) H NMR spectra of the macromonomer PSMA, the graft copolymer PTBA-g-PS and the final purified reaction product poly(acrylic acid-gra/f-styrene) (PAA-g-PS)... 

A novel graft copolymer of hydrophobically modified inuhn (INUTEC SPl) has been used in the emulsion polymerisation of styrene, MMA, butyl acrylate, and several other monomers [8]. All lattices were prepared by emulsion polymerisation, using potassium persulphate as initiator, and the z-average particle size was determined using PCS electron micrographs were also recorded. 

Table XI. Graft Copolymerization of Poly (styrene-alt-acrylonitrile) onto Poly (butyl acrylate) ...

ABS-type resins are used as impact modifiers for PVC, but the resultant blend has insufficient transparency for application in clear bottles. Transparency can be obtained by grafting PMMA onto crosslinked PBD (5) or poly (butyl acrylate) (6) which has been previously grafted onto PS (Diagram 4). In this case the PMMA branch is compatible with PVC by virtue of its solubility parameter, and optical clarity results from suitable component ratios in the graft copolymer so that the refractive index matches that of PVC. The desired results are not obtained if a copolymer of methyl methacrylate and styrene is... 

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