Polymerization lauryl acrylate

Lauryl Acrylate Polymerization by Photo-activated Trigonal 14 Initiation. A more extensive preliminary study of the capability of calorimetry to follow rapid photopolymerization reactions was made of the kinetics of LA polymerization initiated by photo-activated TR-14. 

Figure 2. Photopolymerization exotherm trace. Rate of sample heat change vs. time at 40° C. Photoactivated Trigonal 14 initiation of lauryl acrylate polymerization.

Figure 5. Total heat oj reaction, — plotted against initial T otud 14 concentration, C, for lauryl acrylate polymerizations Table III). , Series W , Series V O, Series VI t). Series VII.

Figure 8. Exotherm rates, (—dH/dt)tx, vs. residual polymerization heats, Hg(tj.), for Series V lauryl acrylate polymerizations. Points correspond to 0.2, 0.3, 0.4, etc., fractional conversions for each run based on its total —AH,.

Lauryl acrylate polymerizations initiated by a photo-activated mixture of benzoin butyl ethers (Trigonal 14) were performed in Perkln-Elmer model DSC-IB and DSC-2 apparata modified by attachment of a heat-filtered medium pressure mercury lamp. Within specified variable limits, the rate of polymerization may be approximated by the relation Rp = const. 0.55 q0.35 2m]. 6 -316/T I js light intensity C is initiator concentration CM] is monomer concentration T is absolute temperature. 

Figure 6. Exotherm rate at peak, —dH/dt (peak), vs. incident light intensity for photoactivated Trigonal 14 initiated lauryl acrylate polymerizations (cf. Table TV). 0, Series VIII O, Series IX and Series X.

Another successful example is the separation of a series of steroids listed in Fig. 6.11 using a monolithic capillary column prepared by redox initiated polymerization of a solution of acrylamide 4, methylene bisacrylamide 5, vinylsulfonic acid 12, and dodecyl acrylate 18 in N-methylformamide/TRIS-boric acid buffer (pH 8.2) to which polyethylene glycol) (MW 10,000) was added (overall composition 5% T, 60% C, 10% vinylsulfonic acid, 15% lauryl acrylate, 3% polyethylene glycol)). The capillary tube was first vinylized and its part beyond the detection window was coated with linear polyacrylamide to avoid band broadening. Since laser induced fluorescence was used to decrease the detection limit of the method to about 100 attomoles for neutral steroids, all of the analytes were first tagged with dansylhydrazine. Fig. 6.12 shows an... 

Materials. Lauryl acrylate was freed of inhibitor by three separatory funnel extractions with 5/f sodium carbonate solution, three deionized water washings, followed by three crystallizations from methanol. Residual methanol and water were removed by 24 hour sparging with nitrogen at room temperature. Both original (inhibited) and purified lauryl acrylate (LA) were polymerized. 

The results of peroxide initiated and Trigonal 14 photoiniti-ated polymerizations of lauryl acrylate (LA), I,6-hexanediol diacrylate (HDDA), neopentyl glycol diacrylate (NPGDA), and trimeth-ylol propane triacrylate (TMPTA) will first be presented. These experiments were designed to observe total heats of polymerization under prescribed conditions. The results of more extensive rate studies on Trigonal 14 photolnitlated LA polymerizations will then follow. 

Summary. The foregoing sections lead to the conclusion that for the photo-activated Trigonal 14 polymerization of lauryl acrylate, the rate of polymerization may be approximately expressed as... 

Polymerization Rate Dependence on Residual Polymerization Heat Lauryl Acrylate Photopolymerization... 

Figure 4. Dependence of —dH/dt exotherm rate at peak on initial Trigonal 14 concentration in photo-polymerizations of lauryl acrylate. , 800 + W, inhibited monomer, T = 52°C, DSC-1B O, 800 + W, T = 30° (Series IV) 3, 400W, T — 40°C (Series V) , 400W, 0.1 neutral density filter, T = 40°C (Series VI).

Bon, Keddy, and coworkers [109] demonstrated that soft armored polymer latex made via Pickering miniemulsion polymerization [i.e., poly(lauryl acrylate) armored with Laponite clay discs] could be used as a nanocomposite additive in standard poly(butyl acrylate-co-acrylic acid) waterborne pressure-sensitive adhesives (PSAs), leading to marked mechanical property enhancements (see Fig. 13). 

Chem. Descrip. Sodium lauryl/propoxy sulfosuccinate Uses Emulsifier for acrylic, vinyl acrylic polymerization Properties Vise. 16,000 cps surf. tens. 31.0 dynes/cm (1%) Ross-Miles foam 163 mm (initial, 1%, 49 C) 60% solids Emcol 4930,4940 [Witco ]... 

Up to now, poly(methyl methacrylate) and methyl methacrylate copolymers e.g. with styrene, butyl acrylate and dodecyl methacrylate) have been the most widely used acrylic polymers for nanocomposite preparation by emulsion and suspension polymerization. Less research has been based on other acrylic polymers, such as polyacrylonitrile, poly(butyl acrylate), " poly(butyl methacrylate), poly(2-ethylhexyl acrylate), poly(2-hydroxyethyl methacrylate), polyacrylamide, poly(lauryl acrylate)," poly(butyl acrylate-co-styrene)," " poly(acrylonitrile-co-styrene), poly(acrylonitrile-co-meth-acrylate)," poly(ethyl acrylate-co-2-ethylhexyl acrylate)" and poly(2-ethylhexyl acrylate-co-acrylic acid)," and sometimes small amounts of hydophilic acrylic monomers, such as hydroxyethyl methacrylate, methacrylic acid and acrylic acid, have been used as comonomers. " Therefore, it may be stated that, so far, the preparation of acrylic-clay nanocomposites has been based mainly on high glass transition temperature polymers, although nanocomposite materials with lower glass transition temperatures with improved or novel properties, which exhibit a balance of previous antagonistic properties, can also be achieved and are very desirable. Regarding nanocomposites of low glass transition temperature polymers, such as poly(butyl acrylate), poly(ethyl acrylate) and poly(2-ethylhexyl acrylate), which have been utilized as the main components of acrylic pressure-sensitive adhesives, little information is available. 

Wang et al. succeeded in preparing waterborne PSAs with nanostructured features that ean build in an energy dissipation mechanism without stiffening the structure too much. In their study, soft-hard polymer particles having Laponite clay armor were synthesized by the Pickering miniemulsion polymerization of -lauryl acrylate (LA). The resulting poly(lauryl acrylate) (PLA)-Laponite hybrid particles were then blended at various low concentrations with... 

Group-Transfer Polymerization. Living polymerization of acrylic monomers has been carried out using ketene silyl acetals as initiators. This chemistry can be used to make random, block, or graft copolymers of polar monomers. The following scheme demonstrates the synthesis of a methyl methacrylate—lauryl methacrylate (MMA—LMA) AB block copolymer (38). LMA is CH2=C(CH2)COO(CH2) CH2. 

Thus these characterization results not only give the distribution of the acrylic acid between the aqueous serum, particle surface, and particle interior, but also account satisfactorily for the total number of strong-acid groups arising from the anionic emulsifier and initiator. In addition, both the sodium lauryl ether sulfate and the nonylphenol polyoxyethylene adduct used in the polymerization were recovered from the fractions obtained by serum replacement. 

Vinyl acetate-butyl acrylate copolymers (0-100% butyl acrylate) were prepared by both batch and starved semi-continuous polymerization using sodium lauryl sulfate emulsifier, potassium persulfate initiator, and sodium bicarbonate buffer. This copolymer system was selected, not only because of its industrial importance, but also because of its copolymerization reactivity ratios, which predict a critical dependence of copolymer compositional distribution on the technique of polymerization. The butyl acrylate is so much more reactive than the vinyl acetate that batch polymerization of any monomer ratio would be expected to give a butyl acrylate-rich copolymer until the butyl acrylate is exhausted and polyvinyl acetate thereafter. 

Aramendia et al. [20] have compared the nonreactive sodium lauryl sulfate (SLS) to the polymerizable sodium tetradecyl maleate (M14), synthesized according to the procedure described by Stahler [21] in the seeded polymerization of methyl methacrylate/butyl acry-late/acrylic acid using tert-butyl hydroperoxide and ascorbic acid as initiator. Nonyl phenol 30 EO (NP30) was the nonionic surfactant used in the seed latex. Latex characterization... 

Effect of Peroxides. In addition to benzoyl peroxide, lauryl-, acetyl-, 2,4-dichlorobenzoyl-, and methyl ethyl peroxide, and tert-hvXy hydroperoxide were studied and gave satisfactory results. The effectiveness of the peroxide is relatively independent of the half-life of the peroxide (Table X). By contrast, the catalyst AIBN is much less satisfactory, as found for methylvinylpyridine and acrylonitrile. The difference between these peroxides and AIBN suggests that the AFR polymer is not formed by a simple uncatalyzed free radical system which would give a graft polymer or a simple mixture of polypropylene and polyacrylate. It is well known that for the polymerization of acrylates AIBN is at least as good if not better than peroxide in initiating the free radical reaction (2). 

As a model monomer for radical homopolymerization of hydrophobic monomers, styrene is described in many papers. The polymerization of acrylates and methacrylates is also well known. It could also be shown that the miniemulsion process also easily allows the polymerization of the ultrahydrophobic monomer lauryl methacrylate without any carrier materials as necessary in emulsion polymerization [71]. 

The chain tacticity of PMMA synthesized by GTP catalyzed by nucleophiles at different temperatures was analyzed by Webster and coworkers The syndiotactic content increases from 50% at 60 °C up to 80% at —90°C in THF, using tris(dimethylamino)sulfonium bifluoride [(Me2N)3S+ HF2 ] as catalyst . In contrast to the anionic polymerization of MMA, the stereoselectivity of GTP is less sensitive to solvent. It must be noted that PMMA is less syndiotactic when the GTP is catalyzed by nucleophiles rather than by Lewis acids . GTP was extended to the living polymerization of many acrylates and methacrylates, such as nBuMA, glycidyl-MA, 2-ethylhexyl-MA, Me3SiOCH2CH2-MA, sorbyl-MA, allyl-MA, lauryl-MA), acrylates (EA, BuA), acrylonitrile, methacrylonitrile and Al,A-dimethylacrylamide . 

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