Styrene-ethyl acrylate copolymer

Applications Radiotracer measurements, which combine high sensitivity and specificity with poor spatial resolution, have been used for migration testing. For example, studies have been made on HDPE, PP and HIPS to determine effects of manufacturing conditions on migration of AOs from plastic products into a test fat [443]. Labelled antioxidant was determined radio-analytically after 10 days at 40 °C. Acosta and Sas-tre [444] have used radioactive tracer methods for the determination of styrene ethyl acrylate in a styrene ethyl acrylate copolymer. 

This study of the chemical composition of styrene-ethyl acrylate copolymers as a function of their molecular weight fractions show a broader molecular weight distribution for ethyl acrylate-rich copolymers than for styrene-rich copolymers. 

Figure 2. The 13C NMR spectrum of a 50/50—styrene/ethyl acrylate copolymer prepared using a conventional uniform monomer feed process...

Figure 5. Linear power feed profile for a 50/50—styrene/ethyl acrylate copolymer in which ethyl acrylate decreases 1.0 -> 0 and styrene increases 0 -> 1.0 with...

Figure 9. Correlation of calculated and measured triad fractions for a model 50/50—styrene/ethyl acrylate copolymer prepared with a linear power feed profile in which ethyl acrylate increases 0—> 1.0 and styrene decreases 1.0 — 0 with time (n = 0.16 r2 = 0.82 (A) EA-EA-EA EA-EA-STY = STY-EA-EA ...

Figure 3. HPLC-chromatogram of styrene-ethyl acrylate copolymers at different compositions and high conversion. Also shown is the styrene content obtained by HPLC calibration -) and on-line HPLC- H NMR experiments (o). (Reprinted from MacromolChem.Phys, Vol.201, LKramer, W.HiUer, H. On-line coupling of gradient-HPLC and NMR for the analysis of random poly[(styrene)-co-(ethyl acrylate)]s , 1662-1666, 2001, with permission from Wiley-VCH)...

Figure 3, i.e., 50/50-styrene/ethyl acrylate copolymer made by uniform (random), staged, or power feed processes (24). Using the carbonyl carbon of the acrylate ester as a probe of the sequence distributions in a series of random styrene/ethyl acrylate copolymer, assignments were made for the three major resonance regions in terms of triad sequences. Figure 6 illustrates the differences observed. In the... 

Brar and Sunita [135] used C-NMR to determine sequence distributions in styrene-ethyl acrylate copolymers. 

Figure 4 Overlay of five HPLC separations of styrene-ethyl acrylate copolymers. The average styrene contents and the standard deviation bars are given. Stationary phase Luna Cl 8100 A, 30 mm x 4.6 mm i.d. mobile phase THF-ACN gradient nominal styrenecontent of the copolymers 0 mol.%...

This type of adhesive is generally useful in the temperature range where the material is either leathery or mbbery, ie, between the glass-transition temperature and the melt temperature. Hot-melt adhesives are based on thermoplastic polymers that may be compounded or uncompounded ethylene—vinyl acetate copolymers, paraffin waxes, polypropylene, phenoxy resins, styrene—butadiene copolymers, ethylene—ethyl acrylate copolymers, and low, and low density polypropylene are used in the compounded state polyesters, polyamides, and polyurethanes are used in the mosdy uncompounded state. 

A number of thermosetting acrylic resins for use as surface coatings have appeared during recent years. These are generally complex copolymers and terpolymers such as a styrene-ethyl acrylate-alkoxy methyl acrylamide... 

Styrene/ethyl acrylate random copolymers were prepared with ethyl acrylate..contents of 10,25,50,75 and 90% by weight. Examination of the 3C NMR spectra of the copolymers reveals that the carbonyl carbon of the acrylate ester is a sensitive probe of the sequence distribution in these copolymers. Figure 2 shows the carbonyl carbon resonance region for a sample containing 50%... 

The freeze/thaw (F/T) stability of a polymer emulsion serves as a macroscopic probe for investigating the properties of the average particle in a polymer emulsion. A review of the factors which contribute to this stability is included. A study of styrene-ethyl acrylate-methacrylic acid polymers shows the existence of a minimum in the plot of minimum weight percent acid required for F/T stability vs. the minimum film formation temperature (MFT) of the polymer. This is considered to be a function of both the amount of associated surfactant and the minimum acid content. Thus, both the type of surfactant and the copolymer ratio—i.e., MFT—play major roles. Chain transfer between radicals and polyether surfactant resulting in covalently bonded surfactant-polymer combinations is important in interpreting the results. 

Styrene—Ethyl Acrylate (S—EA) Copolymers. At the inception of the research on F/T stability, it was evident that more than one polymer system would require investigation before adequate conclusions could be drawn regarding the various pertinent parameters. These include, in addition to the previous considerations, surfactant type and amount as a function of polymer type. 

To this end, work has been initiated on a series of somewhat less polar styrene-ethyl acrylate-methacrylic acid emulsion polymers. The first major difference encountered in changing from the MMA-EA-MAA to the S-EA-MAA polymers was the need for at least a 50% increase in surfactant to obtain a coagulate-free emulsion for the 100% styrene vs. 100% methyl methacrylate. The determination of the minimum weight percent of MAA required to yield a F/T stable emulsion for various copolymers gave the results listed in Table III. 

In another set of carboxylated emulsions prepared with similar Tg, styrene-ethyl acrylate (S-EA) copolymers showed no expansion, but MMA-EA copolymers did. This finding strongly suggested that monomer polarity is also an important factor. The more polar MM A copolymer apparently was able to interact with the highly polar aqueous phase and was thereby plasticized. 

Acrylic elastomer Chlorotrifluoroethylene polymer EPDM rubber Ethylene/ethyl acrylate copolymer Polyvinyl chloride pPDI-PTMEG jSilicone elastomer Styrenated diphenylamine Styrene-ethylene/butylene-styrene block copolymer Tetrafluoroethylene/propylene copolymer gaskets, closure-sealing food containers Arachidyl-behenyl amide Azodicarbonamide Benzyl alcohol Butylene glycol Carbon, activated... 

Copolymer from methyl methacrylate and butyl acrylate Copolymer from methyl methacrylate, butyl acrylate, diallyl maleate, and trimethylol propane triacrylate Methyl methacrylate-ethyl acrylate copolymer Methyl methacrylate-methyl acrylate copolymer Methyl methacrylate-co-A -phenylmaleimide copolymer Copolymer from methyl methacrylate and a-methyl styrene Methyl methacrylate-vinyl acetate copolymer Copolymer of methyl methacrylate, vinyl acetate, and acrylic acid... 

PGC has been used to determine the composition (Le., monomer ratios) of a wide range of copolymers including ethylene-propylene [90, 91], natnral rubber and styrene butadiene rubbers [92, 93], styrene-divinyl benzene [94], polyhexafluoropropylene-vinylidene fluoride [95], acrylic and methacrylic acid [96], PE-ethyl acrylate and PE-vinyl acetate [97], and MMA-ethyl acrylate copolymers [98]. 

Kawai and co-workers [173] determined the composition of butyl acrylate-ethyl acrylate copolymers with a narrow chemical composition distribution by NMR spectroscopy and the components of the copolymers separated by normal and reversed phase high-performance liquid chromatography (HPLC) using crosslinked acrylamide and styrene beads. Samples containing higher butyl acrylate content elnted faster with normal phase HPLC while the opposite occurred with reversed phase HPLC, indicating that butyl acrylate is less polar than ethyl acrylate. 

Coupled HPLC-NMR measurements performed at slow flow rates in fully deuterated solvents and at room temperature have been made in several studies to determine polymer MWD, to analyze the end-groups and the copolymer chemical composition distribution, and to assess the chemical structure and the degree of polymerization of all oligomer species [176-178]. Gradient HPLC-NMR was used in the analysis of the chemical composition distribution of random poly (styrene-co-ethyl acrylate) copolymers [179]. A major drawback in most of these studies is that the measurements could only be conducted at ambient or slightly elevated temperatures, which limits the method applicability, since many polymers, such as polyethylene, polypropylene, and polyolefin copolymers are soluble at high temperatures. 

The hot melt adhesives are based on ethylene-vinyl acetate or ethyl acrylate copolymers or styrene block copolymers, because of the need to adhere to polyester. The starting point formulation for a PET bottle adhesive is given in Table 19 ... 

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