Methylmethacrylate monomers

Graft polymerization of methylmethacrylate monomer onto pulps of different residual lignin contents using ceric ammonium nitrate as the initiator was carried out to study the influence of this residual lignin on the graft-ability of these pulps (Fig. 3). From this figure one can... 

A radical initiator based on the oxidation adduct of an alkyl-9-BBN (47) has been utilized to produce poly(methylmethacrylate) (48) (Fig. 31) from methylmethacrylate monomer by a living anionic polymerization route that does not require the mediation of a metal catalyst. The relatively broad molecular weight distribution (PDI = (MJM ) 2.5) compared with those in living anionic polymerization cases was attributed to the slow initiation of the polymerization.69 A similar radical polymerization route aided by 47 was utilized in the synthesis of functionalized syndiotactic polystyrene (PS) polymers by the copolymerization of styrene.70 The borane groups in the functionalized syndiotactic polystyrenes were transformed into free-radical initiators for the in situ free-radical graft polymerization to prepare s-PS-g-PMMA graft copolymers. 

Figure 31 The radical initiator (47) based on the oxidation adduct of an alkyl-9-BBN used for the production of poly(methyhnethacrylate) (48) from methylmethacrylate monomer by the radical polymerization route. (Adapted from ref. 69.)...

Table 9 Dodecyl mercaptan as costabUizer with methylmethacrylate monomer (from [105]) ...

Bone cement Mixture of polymethylmethacrylate powder and methylmethacrylate monomer liquid to... 

A modified headspace gas chromatographic method has been described for the determination of free methylmethacrylate monomer in contact lenses regardless of their... 

Bradley et al. [69] have extended the sonochemical polymer latex formation technique to synthesise fluorescent and phosphorescent latex particles. The method, schematically shown in Fig. 2.9, simply involved the ultrasonic emulsification of methylmethacrylate monomer in an aqueous surfactant solution where a fluorescence or phosphorescent solute was pre-dissolved in the monomer phase. When pyrene was used as a fluorescent solute, the dielectric constant of the latex particles could be evaluated. Due to the incorporation of the fluorescence solutes into the polymer latex matrix, the interaction between excited state and ground state monomer could be avoided resulting in the lack of dimer emission and domination of monomer emission. 

In cemented total joint arthroplasties, acrylic bone cement functions as the piima ry load bearing material used to transfer loads from the implant to the bone. Bone cement Is formed from an exothermic reaction of benzoyl peroxide initiator present In polymethylmethacrylate powder (PMMA) and AI,AI-dimethyl-p-tolui-dene In methylmethacrylate monomer liquid (MMA), resulting in polymerization of PMMA to form a solid cement matrix. The in vivo integrity and performance of bone cement Is necessary for longevity of orthopedic implants, because it is believed that mechanical failure of the bone cement layer can lead to aseptic loosening of the Implant [101]. 

The major components of the adhesive compositions were stated to be three parts by weight of the BisGMA and one part by weight of methylmethacrylate monomer. In the foregoing BisGMA dental restorative compositions, the low molecular weight methylmethacrylate serves essentially as a reactive extender or diluent to reduce the viscosity of the compositions, whereby they can be conveniently used in dental applications. The benzoyl methyl ether is employed in these compositions as a photosensitizer. Another substance typically used in the dental restorative compositions is benzoyl peroxide, or a similar compound, which serve as a free radical initiator. 

Bone cement Mixture of polymethylmethacrylate powder and methylmethacrylate monomer liquid to be used as a grouting material for the fixation of orthopedic joint implants. 

Two types of ABD-grafted PMMA were initially prepared with different polar and electronic substituents (Fig. 2). ABD-grafted polymer 1 contains no substituent in the azobenzene para position while polymer 2 contains a para nitro group. Potentially, two synthetic routes are possible to generate ABD-grafted PMMA. In approach PMMA is first synthesized and then the ABD is grafted onto the polymer chains. In another approach, ABD-grafted methylmethacrylate monomer units are first synthesized and then polymerized in a subsequent step. 

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