Styrene methacrylate with

Plots of the relationship between the styrene content and retention volume for copolymers of styrene-acrylate and styrene-methacrylate with the same ester group lay roughly on the same line. This result indicates that a pair of copolymers with the same ester group and the same styrene content could not be separated (24), For example, copolymers of styrene-methyl acrylate and styrene-MMA with the same styrene content cannot be separated by this technique. In copolymers with the same styrene content, styrene-butyl acrylate and styrene-butyl methacrylate copolymers eluted first from a column, the copolymers of ethyl esters were next, and those of methyl esters eluted last. 

Acryhc stmctural adhesives have been modified by elastomers in order to obtain a phase-separated, toughened system. A significant contribution in this technology has been made in which acryhc adhesives were modified by the addition of chlorosulfonated polyethylene to obtain a phase-separated stmctural adhesive (11). Such adhesives also contain methyl methacrylate, glacial methacrylic acid, and cross-linkers such as ethylene glycol dimethacrylate [97-90-5]. The polymerization initiation system, which includes cumene hydroperoxide, N,1S7-dimethyl- -toluidine, and saccharin, can be apphed to the adherend surface as a primer, or it can be formulated as the second part of a two-part adhesive. Modification of cyanoacrylates using elastomers has also been attempted copolymers of acrylonitrile, butadiene, and styrene ethylene copolymers with methylacrylate or copolymers of methacrylates with butadiene and styrene have been used. However, because of the extreme reactivity of the monomer, modification of cyanoacrylate adhesives is very difficult and material purity is essential in order to be able to modify the cyanoacrylate without causing premature reaction. 

Polymers containing oxazoline groups are obtained either by grafting the 2-oxazoline onto a suitable existing polymer such as polyethylene or polyphenylene oxide or alternatively by copolymerising a monomer such as styrene or methyl methacrylate with a small quantity (<1%) of a 2-oxazoline. The grafting reaction may be carried out very rapidly (3-5 min) in an extruder at temperatures of about 200°C in the presence of a peroxide such as di-t-butyl peroxide Figure 7.13). 

Hepuzer et al. [91] have used the photoinduced homolytical bond scission of ACPB to produce styrene-based MAIs. These compounds were in a second thermally induced polymerization transferred into styrene-methacrylate block copolymers. However, as Scheme 24 implies, benzoin radicals are formed upon photolysis. In the subsequent polymerization they will react with monomer yielding nonazofunctionalized polymer. The relatively high amount of homopolymer has to be separated from the block copolymer formed after the second, thermally induced polymerization step. 

We extended the kinetic model to other monomer systems such as styrene and methyl methacrylate. With these, we used common initiators such as benzoyl peroxide and azo-bis-isobutyronitrile. The results of these simulations compared closely with some published experiments. 

Fig. 8.—Log-log plot of initial polymerization rates Rj, in moles/Z./sec. against the initiator concentration [I] in moles/Z. Line 1, methyl methacrylate using azo-bis-iso-butyronitrile at 50°C.26 Line 2, styrene with benzoyl peroxide at 60°C.25 Line 3, methyl methacrylate with benzoyl peroxide at 50°C. ...

Brown and White employed this approach to prepare block copolymers of styrene and mcthacrylic acid (6). They were able to hydrolyze poly(styrene-b-methyl methacrylate) (S-b-MM) with p-toluenesulfonic acid (TsOH). Allen, et al., have recently reported acidic hydrolysis of poly(styrene-b-t-butyl methacrylate) (S-b-tBM) (7-10). These same workers have also prepared potassium methacrylate blocks directly by treating blocks of alkyl methacrylates with potassium superoxide (7-10). 

Our requirements for certain applications called for the preparation of block copolymers of styrene and alkali metal methacrylates with molecular weights of about 20,000 and methacrylate contents of about 10 mol%. In this report we describe the preparation and reactions of S-b-MM and S-b-tBM. In the course of our investigation, we have found several new methods for the conversion of alkyl methacrylate blocks into methacrylic acid and/or metal methacrylate blocks. Of particular interest is the reaction with trimethylsilyl iodide. Under the same mild conditions, MM blocks are completely unreactive, while tBM blocks are cleanly converted to either methacrylic acid or metal methacrylate blocks. As a consequence of this unexpected selectivity, we also report the preparation of the new block copolymers, poly(methyl methacrylate-b-potassium methacrylate) (MM-b-MA.K) and poly(methyl methacrvlate-b-methacrylic acid) (MM-b-MA). 

Preparation and Reactions of S-b-MM. As mentioned in the introduction, we were interested in block copolymers of styrene and alkali metal methacrylates with overall molecular weights of about 20,000 and methacrylate contents on the order of 10 mol%. The preparation of such copolymers by the usual anionic techniques is not feasible. An alternative is to prepare block copolymers of styrene and methacrylic esters by sequential anionic polymerization, followed by a post-polymerization reaction to produce the desired block copolymers. The obvious first choice of methacrylic esters is methyl methacrylate. It is inexpensive, readily available, and its block copolymers with styrene are well-known. In fact, Brown and White have reported the preparation and hydrolyses of a series of S-b-MM copolymers of varying MM content using p-toluenesulfonic acid (TsOH) (6). The resulting methacrylic acid copolymers were easily converted to their sodium carboxylates by neutralization with sodium hydroxide. 

At this point a comparison of these observations with those reported by Allen, et al. (7-10), for the reaction of poly(styrene-b-isobutyl methacrylate) with potassium superoxide should be made. 

A considerable viscosity increase in copolymers of tributylstannyl methacrylate with methyl methacrylate, butyl acrylate and styrene upon prolongated storage has been observed and special agents to eliminate this effect have been proposed 108). It is likely that the destruction of intermolecular coordination complexes formed by involvement of tin and carbonyl groups in comonomer units takes place in this case. 

Table IX. Synergistic Effect of Multifunctional Methacrylates with Inorganic Salts(L) in Grafting Styrene to Polypropylene Initiated by UVa ...

These were obtained by copolymerization of styrenic macromonomers containing dendritic pendant groups with styrene [16a] with a later extension to methacrylate-type copolymers [16b]. As these studies were carried out with... 

The ability to conduct radical reactions without the use of tin reagents is important. Allylic triflones have been used to conduct allylation reactions on a range of substrates (39) as a replacement for allyltributylstannane (Scheme 28). The main limitation was that unactivated or trisubstituted triflones failed to undergo reactions. In other nontin radical methods, arenesulfonyl halides have been used as functional initiators in the CuCl/4,4 -dinonyl-2, 2 -bipyridine-catalysed living atom-transfer polymerization of styrenes, methacrylates, and acrylates.The kinetics of initiation and propagation were examined with a range of substituted arylsulfonyl halides with initiator efficiency measured at 100%. 

A special case of asymmetric enantiomer-differentiating polymerization is the isoselective copolymerization of optically active 3-methyl-1-pentene with racemic 3,7-dimethyl-1-octene by TiCl4 and diisobutylzinc [Ciardelli et al., 1969]. The copolymer is optically active with respect to both comonomer units as the incorporated optically active 3-methyl-l-pentene directs the preferential entry of only one enantiomer of the racemic monomer. The directing effect of a chiral center in one monomer unit on the second monomer, referred to as asymmetric induction, is also observed in radical and ionic copolymerizations. The radical copolymerization of optically active a-methylbenzyl methacrylate with maleic anhydride yields a copolymer that is optically active even after hydrolytic cleavage of the optically active a-methylbenzyl group from the polymer [Kurokawa and Minoura, 1979]. Similar results were obtained in the copolymerizations of mono- and di-/-menthyl fumarate and (—)-3-(P-styryloxy)menthane with styrene [Kurokawa et al., 1982],... 

Figure 8 (1., 6) shows the fractionation obtained by analyzing a mixture of polystyrene, poly(styrene co-n-butyl methacrylate) and poly(n-butyl methacrylate) with various n-heptane concentrations. 

Since the late 1960 s a few papers have demonstrated compositional analysis of various polymer systans by Raman spectroscopy. For example, Boerio and Yuann (U) developed a method of analysis for copolymers of glycidyl methacrylate with methyl methacrylate and styrene. Sloane and Bramston-Cook (5) analyzed the terpolymer system poly(methyl methacrylate-co-butadiene-co-styrene). The composition of copolymers of styrene-ethylene dimethacrylate and styrene-divinylbenzene was determined by Stokr et (6). Finally, Water (7) demonstrated that Raman spectroscopy could determine the amount of residual monomer in poly(methyl methacrylate) to the % level. This was subsequently lowered to less than 0.1% (8). In spite of its many advantages, the potential of Raman spectroscopy for the analysis of polymer systems has never been fully exploited. 

The attractions of a drying agent which forms a homogeneous mixture with the substance to be dried, e.g. triethyl aluminium or dibutyl magnesium with hydrocarbons and some other compounds, are obvious the former can be used with methyl methacrylate, the latter with styrene and with dienes. However, it is questionable whether the difficulty of separating the dried compound completely from unused drying agent and the fire-hazard associated with many metal alkyls make the effort worth while, except in some special cases. 

The chain transfer reaction played an important role, particularly because of abstraction of the active hydrogen at a-carbon from the allyl group. Moreover, unreacted double bonds were present in the copolymer obtained. The influence of chain transfer reaction could be diminished by applying multimonomers which do not contain allyl groups. This was shown in the example of copolymerization of multimethacrylate prepared by esterification of poly(2-hydroxyethyl methacrylate) with methacryloyl chloride. Copolymerization of the multimethacrylate with vinyl monomers such as styrene or acrylonitrile can be represented by the reaction ... 

Copolymerization of methyl methacrylate with styrene in the presence of isotactic poly(methyl methacrylate) has been examined by O Driscoll and Capek. Copolymerization was carried out in acetone at O C and redox system benzoyl peroxide -dimethylaniline was used to initiate the polymerization process. Carrying out the process with various ratios of styrene to methyl methacrylate, it was found that the polymerization rate drops very quickly with the increase in styrene concentration. A very small amount of styrene destroys any template effect that it-poly(methyl methacrylate) exerts on the rate of the polymerization. Assuming, that the reactivity ratios are not changed by the template (ri = i2 = 0.5), the critical length of the sequence of methacrylic units is 10- 20. Complexation occurs only if longer sequences, composed of methacrylic... 

Ceresa synthetized also block copolymers of poly(methyl methacrylate) with acrylonitrile and styrene and of polyethylene with methyl methacrylate, styrene using this method (104). 

Figure 3. Copolymerization of glucosyloxyethyl methacrylate (GEMA) with other vinyl monomers. (Q) with acrylamide (AAm), (0) with styrene (St), ( ) with acrylonitrile (AN), and ( ) with methyl methacrylate (MMA).

Accordingly, the synthesis of novel cinnamate polymers with high functionality and performance is very important from the viewpoint of both polymer chemistry and practical use. Recently, we have reported the synthesis of polymers with pendant photosensitive moieties such as cinnamic ester and suitable photosensitizer groups by radical copolymerizations of 2-(cinnamoyloxy) ethyl methacrylate with photosensitizer monomers (9), by copolymerizations of chloromethylated styrene with the photosensitizer monomers followed by the reactions of the copolymers with salts of... 

Zinc Nitrate. See in Vol 8, N40-L and the following Addnl Refs 1) G.W. Batchelder G.A. Zimmerman, Smokeless Propellant Compositions Containing a Polyester Resin , USP 3653993 (1972) CA 79,77449 (1973) [The inventors claim that Zn nitrate acts as the burning rate catalyst in their propint formulation. Thus, the addn of 0.1% Zn nitrate to a propint contg AN (45), amm dichromate (5%), a polyester, styrene, methacrylate and lecithin increased this parameter from 0.07 to 0.11 indies/ sec] 2) Anon, Fire Protection. . . 7th Edition , NFPA, Boston (1979), 491M-445 [This source reports that Zn nitrate will expld if sprinkled on hot C. Also, that heat, shock and friction sensitive expls are formed when the nitrate is intimately mixed with the following finely divided materials Cu, metal sulfides, organic matter, P and S]... 

Fig. 30. Chromatographic cross-fractionation of300 mg poly(styrene-6-methyl methacrylate) with 47 wt % styrene. SEC curves of the fractions obtained by column adsorption chromatography. The large SEC curve is from the non-fractionated sample. (From Ref.1321 with permission)...

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