Norbornene terpolymerizations

The cleavable Si group as described above has been also incorporated in a polymethacrylate resist for 193 nm bilayer lithography (Fig. 151) [422b]. In a similar fashion 1,3-bis(trimethylsilyl)isopropyl methacrylate was terpolymerized with methacrylic acid and methyl methacrylate with AIBN in THF [428]. The COMA system has been modified to be used as a bilayer positive resist by incorporating norbornenes bearing a passive Si group and an acid-cleavable Si group (Fig. 152) [429]. 

Scheme 7.36 Synthetic scheme for the polymerization of norbornene and its derivatives via free radical polymerization (FRP), ring-opening metathesis polymerization (ROMP), and vinyl addition polymerization (VAP) techniques. Polymers I, II, and III are isomers that differ in their enchainment and physical properties. Co- and terpolymerization of norbornene and derivatives of norbornene with other alicyclic monomers such as maleic anhydride, methyltetracyclododecene carboxylic acid, etc. are also successfully synthesized with this scheme. (Note that 2, 3- and 2,7-enchainments of repeating units are reported in type I polymers. °°)...

A series of patents were issued to DuPont in the mid-1970s that covered the terpolymerization of ethylene, propylene, and functional monomers. The catalyst employed was a soluble VCl4/AlEt2Cl in combination with hexachloropropene as a catalyst activator. The functional comonomers studied included 2-hydroxy-5-norbornene, 2-hydroxymethyl-5-norbornene, allylsulfonyl chloride, 2-allylphenol, and... 

Radical Co- and Terpolymerization of Norbornenes with SO2. A typical polymerization procedure is described below. The fluoroalcohol monomer la (2.74 g, 0.01 mol) was placed in 25 mL of liquid sulfur dioxide at -60 to which were added... 

Jenner and Kellou recently studied the pressure effect on azeotropy in free-radical terpolymerization of MA with acrylonitrile, dielthyl fumarate, methyl acrylate, methyl methacrylate, methyl vinyl ketone, vinylidene chloride, norbornene, a-methylstyrene, indene, and vinyl acetate, with styrene as the second comonomer common in all cases. It was found that ternary azeotropes were only possible for those systems where the first comonomers had positive e values, i.e., diethyl fumarate, acrylonitrile, methyl acrylate, methyl methacrylate, methyl vinyl ketone, and vinylidene chloride. Surprisingly, the coordinates of the ternary azeotropes were very little affected by variations of the pressure from 1-3,000 bars. Since reactivity ratios in multi-component polymerizations are sensitive to pressure, causing terpolymer composition to also be pressure dependent, a shift of the ternary azeotropic point would be expected. Why this occurs awaits further clarification. 

The scandium complex VIII-1 was used for the first time to achieve copolymerization of ethene with 5-norbornene-2-methanol and terpolymerization of ethene with norbornene and 5-norbomene-2-methanol with these highly sensitive family of catalysts. The requirements for the success were (1) the preactivation by [Ph3C][B(C6F5)4] and (2) the use of isolated APBus-protected monomer. Copolymers with high molar masses up to 330 000 gmol" ) and good incorpora-... 

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