Vinyl isobutyl ether

Poly(isobutyl vinyl ether-covinyl chloride) [25154-85-2]... 

Oral toxicity is very low isobutyl vinyl ether has LD q of 17 mL/kg for white rats. 

The observation in 1949 (4) that isobutyl vinyl ether (IBVE) can be polymerized with stereoregularity ushered in the stereochemical study of polymers, eventually leading to the development of stereoregular polypropylene. In fact, vinyl ethers were key monomers in the early polymer Hterature. Eor example, ethyl vinyl ether (EVE) was first polymerized in the presence of iodine in 1878 and the overall polymerization was systematically studied during the 1920s (5). There has been much academic interest in living cationic polymerization of vinyl ethers and in the unusual compatibiUty of poly(MVE) with polystyrene. 

Methyl vinyl ether Ethyl vinyl ether Isopropyl vinyl ether -Butyl vinyl ether Isobutyl vinyl ether... 

VEs can also copolymerize by free-radical initiation with a variety of comonomers. According to the and rvalues of 0.023 and —1.77 (isobutyl vinyl ether), VEs are expected to form ideal copolymers with monomers of similar and e values or alternating copolymers with monomers such as maleic anhydride (MAN) that have high values of opposite sign (Q = 0.23 e = 2.25). 

A variety of trichloroethylene copolymers have been reported, none with apparent commercial significance. The alternating copolymer with vinyl acetate has been patented as an adhesive (11) and as a flame retardant (12,13). Copolymerization with 1,3-butadiene and its homologues has been reported (14—16). Other comonomers include acrylonitrile (17), isobutyl vinyl ether (18), maleic anhydride (19), and styrene (20). 

Isobutyl vinyl ether [109-53-5] M 100.2, b 108-110 , d 0.768, n 1.398. Washed three times with equal volumes of aqueous 1 % NaOH, dried with CaH2, refluxed with sodium for several hours, then fractionally distd from sodium. 

At -50°C Mn s remained unchanged (Mn % 3 x 10, [p-DCC]Q = 0.50 mM) with increasing Wjgyg and Mw/Mn % 2.0. The polymerization is no longer quasiliving but follows a conventional chain-transfer-dominated course. Nonpolar media are evidently unsuitable for quasiliving polymerization of isobutyl vinyl ethers. 

St styrene, MMA methyl methacrylate, IB isobutene, VAc vinyl acetate, VC1 vinyl chloride, DiPF diisopropyl fumarate, AA acrylic acid, MAn maleic anhydride, IBVE isobutyl vinyl ether. 

The results for the formulations containing isobutyl vinyl ether are shown in Figure 2. Due to the vinyl ether double bond to maleate double bond ratio constraint, the compositions used for this study are located in one comer of the triangular graph. It was unfortunate that compositions containing little or no DVE-3 were incompatible and could not be evaluated. Viscosities were not measured on these formulations. Cure dose increases as the amount of monofunctional diluent increases. Pencil hardness increased as the vinyl ether double bond to maleate double bond ratio increased. These results indicate that substitution of a monofunctional maleate or vinyl ether diluent results in reduced cure speed and pencil hardness. 

Figure 2. Three component study using isobutyl vinyl ether as a diluent.

Maleate/vinyl ether formulations based on a model unsaturated polyester prepared from maleic anhydride and 1,5-pentane diol and triethylene glycol divinyl ether were studied. At molecular weights of less than about 10,000 the cured films were extremely brittle. When the equivalent weight of the unsaturated polyester was increased by replacing some of the maleic anhydride with succinic anhydride, measurable values for film elongation could be obtained but the cure speed was definitely slower. When either diethyl maleate or isobutyl vinyl ether were added as monofunctional diluents the cure dose needed to obtain 200 MEKDR was increased and the flexibility measured by pencil hardness increased as the amount of diluent was increased. A urethane vinyl ether was synthesized and used to replace DVE-3 and films with increased elongation were obtained at equivalent at dosages as low as 1 J/cm2. 

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