Isobutyl methacrylate

Mechanical properties of a hydrogel lens also are affected by the use of a hydrophobic monomer, such as a low alkyl methacrylate. This is particularly important when the water content of the hydrogel lens is very high. The use of these methacrylates helps preserve the required mechanical strength. Methyl methacrylate [80-62-6] (MMA) (I2I), isobutyl methacrylate [97-86-9] (122), and / -pentyl methacrylate [2849-98-1] (123) all have been used for this purpose. 

Park et al. [20] reported on the synthesis of poly-(chloroprene-co-isobutyl methacrylate) and its compati-bilizing effect in immiscible polychloroprene-poly(iso-butyl methacrylate) blends. A copolymer of chloroprene rubber (CR) and isobutyl methacrylate (iBMA) poly[CP-Co-(BMA)] and a graft copolymer of iBMA and poly-chloroprene [poly(CR-g-iBMA)] were prepared for comparison. Blends of CR and PiBMA are prepared by the solution casting technique using THF as the solvent. The morphology and glass-transition temperature behavior indicated that the blend is an immiscible one. It was found that both the copolymers can improve the miscibility, but the efficiency is higher in poly(CR-Co-iBMA) than in poly(CR-g-iBMA),... 

Pyrogels used by the US armed forces include (1) PT1, which is a complex mixt based on a paste of Mg and an oxidizer, bound with petroleum distillate and asphalt. Isobutyl methacrylate is used as a thickener. (2) PT2, which contains 5% isobutyl methacrylate as a thickener, together with Ba nitrate and a small quantity of asphalt. (3) PTV, which is described as an improved oil and metal incendiary mixt composed of 5% poly butadiene, 6% Na nitrate, 28% Mg, and a trace of p-aminophenol in 60% gasoline (Ref 5)... 

The alkyl methacrylate monomers were available from various sources. Isobutyl methacrylate (IBMA) (Rohm and Haas) and t-butyl methacrylate (TBMA) (Rohm Tech) may be purified first by distillation from CaH, followed by distillation from trialkyl aluminum reagents as described in detail earlier (20,21). In particular, t-butyl methacrylate (b.pt. 150°C) was successfully purified by distillation, from triethyl aluminum containing small amounts of diisobutyl aluminum hydride. The trialkyl aluminum and dialkyl aluminum hydride reagents were obtained from the Ethyl Corporation as 25 weight percent solutions in hexane. The initiator, -butyllithium, was obtained from the Lithco Division of FMC, and analyzed by the Gilman "double titration" (22). 

The physical properties of the acid- and ion-containing polymers are quite interesting. The storage moduli vs. temperature behavior (Figure 8) was determined by dynamic mechanical thermal analysis (DMTA) for the PS-PIBMA diblock precursor, the polystyrene diblock ionomer and the poly(styrene)-b-poly(isobutyl methacrylate-co-methacrylic acid) diblock. The last two samples were obtained by the KC>2 hydrolysis approach. It is important to note that these three curves are offset for clarity, i.e. the modulus of the precursor is not necessarily higher than the ionomer. In particular, one should note the same Tg of the polystyrene block before and after ionomer formation, and the extension of the rubbery plateau past 200°C. In contrast, flow occurred in... 

Figure 8. DMTA behavior for poly(styrene)-b-poly(isobutyl methacrylate-co-methacrylic acid) potassium salt.

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. 

They too obtained a product which was poorly soluble in THF and many other solvent combinations. Acidification with HC1 in THF improved the solubility, but the product displayed an IR band at 1730 cm"1 in addition to a methacrylic acid at 1700 cm"1. They attributed the band at 1730 cm"1 to unreacted isobutyl methacrylate groups, but in light of our observations, it may be due to the same type of side-reaction. 

Polyacetal Polyacrylamide Polyacrylonitrile Polycarbonate Polyethylene Polyethylene oxide Polyethylene terephthalate Poly isobutyl methacrylate Poly methacrylic acid Polymethyl methacrylate Polymonochlorotrifluoro ethylene Polypropylene Polystyrene... 

Figure 4. Loss of solubility of Du Pont Elvacite 2046, a 1 1 copolymer of n-butyl and isobutyl methacrylate, with and without UV absorber and antioxidant additives...

C02CH2CH(CH3)2 - poly(Isobutyl methacrylate) (PIBM) C02C(CH3)3- poly(tert-butyl methacrylate) (PTBM) CO2CH2CCI3- poly(trichloroethyl methacrylate) (PTCEM) CO2CH2CF2 poly(trifluoroethyl methacrylate) (PTFEM) C02CH(CF3)2 poly(hexafluoroisopropyl methacrylate)(PHFIM) CN - poly(methacrylonitrile)(PMCN)... 

I. M. Filling. Jellied gasoline filling developed during WWII by Standard Oil Co and used for filling incendiary bombs isobutyl methacrylate polymer 5.0, fatty acids, such as stearic acid,... 

Methacrylic acid Acrylic acid Di-isobutylene Acrylonitrile Allyl acrylate Allyl methacrylate n-Butyi acrylate n-Butyl methacrylate isobutyl methacrylate 2-Chloroethyl methacrylate -Ethoxyethyl methacrylate Ethyl acrylate 2-Ethylhexyl acrylate Ethyl methacrylate Lauryl methacrylate Nonyl methacrylate N-Vinyl pyrrolidone Octyl acrylate 2-Vinyl pyridine... 

Acrylonitrile Allyl acrylate Allyl methacrylate n-Butyl acrylate n-Butyl methacrylate Isobutyl methacrylate Divinyl benzene 2-Choroethyl methacrylate Ethyl acrylate /i-Ethoxyethyl methacrylate 2-Ethylhexyl methacrylate Ethyl methacrylate Methyl methacrylate Methylisopropenylketone Methyl vinyl ketone N-Vinyl pyrrolidone Styrene Vinylpyridine Acrylonitrile Allyl acrylate Allyl methacrylate... 

In addition to MMA, a variety of methacrylic esters were polymerized rapidly to the corresponding polymers with narrow MWDs in the presence of methylaluminum bis(2-ferf-butyl-4-methoxyphenolate) (3c). The successful examples include ethyl methacrylate (EMA), isopropyl methacrylate ( °PMA), n-butyl methacrylate ("BMA), isobutyl methacrylate ( °BMA), benzyl methacrylate (BnMA), and dodecyl methacrylate (Cj2MA), where the Mn values were all close to the predicted values (Mn j ) with the Mw/Mn ratios below 1.1 (Table 3, runs 1-4,6,7). The polymerization of ferf-butyl methacrylate ( BMA) is the only exception, where the monomer conversion hardly increased even after 24 h. 

Figure 15. Influence of the Polyester Yellow dye film absorbance and polymer binder material on the marking threshold energy. PnBMA = poly(n-butyl methacrylate) PiBMA = poly(isobutyl methacrylate) PS = polystyrene PsBMA = poly (sec-butyl methacrylate) PVB = polyvinylbutyl PMMA = polymethyl methacrylate PVAC = polyvinylacetate, S-iBMA = poly(styrene-co-isobutyl methacrylate), PC = polycarbonate S-AN — poly(styrene-co-...

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