N-Butylmethacrylate

Films cast from poly(n-butylmethacrylate) and polymethylmethacrylate)... 

Frechet and coworkers recently described how living free radical polymerization can be used to make dendrigrafts. Either 2,2,6,6-tetramethylpiperidine oxide (TEMPO) modified polymerization or atom transfer radical polymerization (ATRP) can be used [96] (see Scheme 10). The method requires two alternating steps. In each polymerization step a copolymer is formed that contains some benzyl chloride functionality introduced by copolymerization with a small amount of p-(4-chloromethylbenzyloxymethyl) styrene. This unit is transformed into a TEMPO derivative. The TEMPO derivative initiates the polymerization of the next generation monomer or comonomer mixture. Alternatively, the chloromethyl groups on the polymer initiate an ATRP polymerization in the presence of CulCl or CuICl-4,4T dipyridyl complex. This was shown to be the case for styrene and n-butylmethacrylate. SEC shows clearly the increase in molecu-... 

Experimental data for polymer solutions have been reported by Osaki, Tamura, Kurata, and Kotaka (60), by Booij (12), and by Macdonald (50). Osaki et al. used polystyrene in toluene, polymethylmethacrylate in diethylphthalate, and poly-n-butylmethacrylate in diethylphthalate. Booij s data were for aluminum dilaurate in decalin and a rubbery ethylene-propylene copolymer in decalin. Macdonald s experiments were performed on several polystyrenes in several Aroclors and on polyisobutylene in Primol. Shortly after the original publication of the Japanese group, Macdonald and Bird (51) showed that a nonlinear viscoelastic constitutive equation was capable of describing quantitatively their data on both the non-Newtonian viscosity and the superposed-flow material functions. Other measurements and continuum model calculations have been described by Booij (12 a). 

In the early stages of degradation, polymethyl-a-phenylacrylate [97, 98] decomposes by random initiation and unzipping to monomer, as do poly-a-methylstyrene and anionic polymethylmethacrylate. Later in the reaction, chain-end initiation becomes important and predominates beyond about 45% conversion. Poly-n-butylmethacrylate yields appreciable amounts of monomer but the reaction is not quantitative [99]. Monomer production ceases at 30—50% conversion at 250° C, and at... 

Monomer production is a general reaction of the methacrylates. Ester decomposition yielding methacrylic acid and the corresponding olefin is possible when the alcohol residue has P hydrogen atoms it becomes the most important mechanism in the case of tertiary esters like poly-t-butylmethacrylate but is competitive with monomer formation in ethyl- and n-butylmethacrylates. 

Other polymers which degrade in organic solutions include poly-n-butylmethacrylate [450] and copolymers of styrene and a-methylstyrene [451],... 

Certain organic compounds like DHI can develop colour in snnlight and lose it in the dark (photochromic material). DHI is commonly used with a range of different polymers, such as polymethylmethacrylate (PMMA), poly-n-butylmethacrylate (P(nBMA)) and polystyrene-polybutadiene (PS-BD) copolymers. Their applications include eye-glasses, light modulators, inks, paints and optical waveguides. 

Chem. Descrip. N-Butylmethacrylate/MMA Uses Binder for metal lacquers, marine and road marking paints, exterior wall paints, and concrete coatings food-contact coatings... 

Zimmerman and co-workers reported a similar quadmple complementary H-bonding pair (designed to minimize homodimerization of one of the units) with very high Ka values (3 X 10 M" ) used to prepare a styrenic and methacrylate monomer subsequently copolymerized with styrene and n-butylmethacrylate, respectively, via traditional free-radical polymerization. Blends of the polymers clearly formed networks in the bulk and in chloroform solutions. 

The chemical modification of homopolymers such as polyvinylchloride, polyethylene, poly(chloroalkylene sulfides), polysulfones,poly-chloromethylstyrene, polyisobutylene, polysodium acrylate, polyvinyl alcohol, polyvinyl chloroformate, sulfonated polystyrene block and graft copolymers such as poly(styrene-block-ethylene-co-butylene-block-styrene), poly(1,4-polybutadiene-block ethylene oxide), star chlorine-telechelic polyisobutylene, poly(lsobutylene-co-2,3-dimethy1-1,3-butadiene), poly(styrene-co-N-butylmethacrylate) cellulose, dex-tran and inulin, is described. 

Results were presented from ID solid-state NMR MAS exchange nuclear experiments aimed to investigate the influence of the side-chain length on the main- and side-chain dynamics in selected members of the poly- -acrylates series, poly( -hexylmethacrylate) and poly(n-butylmethacrylate). The molecular dynamics of the different molecular sub-units in the slow-motion region was... 

In this chapter, single-component reactions are discussed. To model the extruder as a reactor for this kind of reaction, a complex interaction of reaction and extruder parameters has to be unraveled [7,8]. As an example of a single-component reaction the polymerization of n-butylmethacrylate is studied and analyzed. 

The bulk polymerization of n-butylmethacrylate is a free-radical addition polymerization. With this type of single-component reaction, polymer chains are formed in a relatively short time and are subsequently excluded from... 

Kinetic experiments with n-butylmethacrylate (n-BMA) have been described in literature in a temperature range of 80-130°C [5,14]. As the extruder temperatures are in the range of 110-130°C, especially the experiments of Ganzeveld and Janssen [5] are relevant for the understanding of the influence of the gel effect on the reaction at higher temperatures. They performed isothermal differential scanning calorimetry (DSC) measurements at temperatures of 110°C, 120°C, and 130°C with n-butylmethacrylate (inhibited) and a combination of two initiators. The inhibitor was not removed from the monomer to imitate the situation in the extruder. The initiators were peroxides with half-life times of 1 hr at 92°C and 132°C and concentrations of 1.2% and 0.5% that were well mixed with the monomer in order to prevent diffusion limitations. 

Fig. 3 The influence of the temperature on the conversion curve of n-butylmethacrylate. +, A, and V measured values — theory according to eq. (4).

The influences of the reaction and extruder parameters on the reaction process in the extruder were investigated by doing experiments with n-butylmethacrylate in a counterrotating twin screw extruder [5]. Several parameters were changed, such as the rotation rate of the screws, the throughput, the die resistance, and, as a consequence, the fully filled length of the extruder. 

The experimental setup consisted of feeding a mixture of n-butylmethacrylate (inhibited), with a combination of a fast initiator and a slow initiator to the extruder, at room temperature. The use of a fast initiator assures a start of the reaction at relatively low temperatures and, therefore, decreases the maximum temperature in the extruder, whereas the slow initiator is still active toward the end of the process, when temperatures are high. The mixture and the extruder were both flushed with nitrogen to prevent an extra inhibition of the reaction by a reaction of oxygen with the radicals. 

There is a limited number of studies of adsorption of diblock copolymers from nonselective solvents. One practical problem is that it is not enough to find a nonselective solvent, but that a brush-like configuration also requires selective adsorption of the A block. Because polymers are notorious for adsorbing onto many substrates [3,41], the best way is to use a mixed solvent with a composition such that A adsorbs and not B. Some early data were obtained by Wu et al. [19] for diblocks of dimethyl-aminoethyl-methacrylate (A) and n-butylmethacrylate (B) from propanol onto silica. For chains of 200 and 700 monomers, Wu et al. found a clear maximum at around 10% of A monomers, where the adsorbed amormt reaches a value of 13 mg/m. This behavior was thus very much in line with the theoretical predictions, as shown in Figure 7.2. The adsorbed amount of 13 mg/m corresponds with a grafting density of about 1 chain per 10 nm, which is reasonable but not very dense. Later experiments on diblocks with a cationic block (dimethyl-aminoethyl-methacrylate (AMA)) and a neutral block (dihydroxy-propyl-methacrylate (HM A)) on silica and titania were carried out by Floogeveen et al. [42] (Figure 7.3). 

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