BPA/DC prepolymer

Solvent resistant laminates for printed circuits were manufactured by coating of copper foil with a solution of PPO, BPA/DC, bis(4-maleimidophenyl) ether and Zn octoate in toluene the coated foil was laminated with PPO-impregnated glass fabric [47]. Similar result was achieved by the modification of PPO with polyfunctional cyanates or maleimides, liquid polybutadiene and a polymerization catalyst [48], A solvent and heat resistant composition for printed circuits consists of copoly [(2,6-dimethylphenylene)-(2,3,6-trimethylphenylene)]oxide, maleic anhydride grafted poly-1,2-butadiene, bis(4-maleimidophenyl)methane, BPA/DC and toluene. BPA/DC prepolymer may be used instead of the monomer [49]. 

In several patents, the application of BPA/DC prepolymer in epoxide resin compositions is described [79, 81-84], This approach is similar of that mentioned in the chapter devoted to cyanate/maleimide compositions [62],... 

As an additional component, various thermoplastic polymers can be used. As a binder for copper clad laminates, a solution of solid epoxide resin (Epikote 1001), BPA/DC prepolymer, Zn acetate and poly(phenylene sulfide) was used [83], Other binders for reinforced plastics contain polysulfone. Such compositions consist of liquid BPA/ECH epoxide resin, BPA/DC prepolymer, polysulfone and bis(4-hydro-xyphenyl)sulfone [85]. Bis(4-aminophenyl)sulfone can be also added [86]. In such systems the bisphenol reacts with the epoxide resin as a chain extension agent, whereas the diamine crosslinks the diepoxide. The Tg values are close to 200 °C. They can be increased a little, if the BPA/ECH epoxide resin is replaced by the tetra-epoxide A,A,A, A -tetrakis(2,3-epoxypropyl)diaminodiphenylmethane [87]. 

A typical three-component composition consists of BPA/DC prepolymer, bis(4-maleimidophenyl)methane (BMI), epoxide resin, Zn acetate and triethylenediamine in methylethylketone [93]. 

A binder was obtained from an epoxynovolak resin, BPA/DC, BMI, dicyclopenta-diene, Zn acetate and dicumyl peroxide [94]. In a similar composition, BPA/DC prepolymer was used as curing and cyclotrimerization initiators and catalysts, catechol, triethylenediamine, Zn acetate and benzoyl peroxide are mentioned [95], Other compositions contain A1 acetylacetonate and a silicone resin [96], p-toluenesulfonic acid monohydrate and Zn octoate (for rapid curing) [97], or dicumyl peroxide and Zn octoate [98]. 

Fire resistant polymers were obtained from brominated epoxynovolak resin, BPA/DC prepolymer, BMI, Zn acetate and benzoyl peroxide [103] or from an oligo-aspartimide (BMI-diamine reaction product), BPA/DC, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane (i.e. Tetrabromo-Bisphenol A) and 2-ethyl-4-methylimi-dazole [104]. A mixture of BPA/DC, BMI and epoxide resin with brominated polycarbonate, copoly[oxy-2,6-dimethylphenylene)-(oxy-2,3,6-trimethylphenylene)] and a catalyst was also suggested [105],... 

Curing of multicomponent systems consisting of BPA/DC, BMI and diallyl or triallyl esters (triallyl isocyanurate TAIC in particular) results in high Tgvalues. Such compositions consist of BPA/DC, BMI, TAIC, diallyl phthalate and dicumyl peroxide [127], BPA/DC prepolymer, BMI, TAIC, /erf.butyl peroxide, Zn acetate and DABCO [128] or BMI/trimethylene bis(4-aminobenzoate) prepolymer, BPA/DC, Zn octoate and TAIC [129]. 

Some dicyanate-containing compositions, which contain rubbers as flexibilizing components, were described in the preceding chapters. There were also patent applications made, where dicyanates were claimed as additives in typical rubber mixtures. In such mixtures, butadiene-acrylonitrile rubber is used. The main components of such binders are nitrile rubber, BPA/DC and methylethylketone. They contain, moreover, Zn octoate and Fe203 [144] or ZnO and sulfur [145]. Isoprene-acryloni-trile rubber, BPA/DC prepolymer, Zn octoate, DABCO and benzoyl peroxide were dissolved in a methylethylketone-dimethylformamide mixture. Glass fiber was impregnated with the obtained solution [146]. 

T ransparent heat resistant coatings were formed by heating of a mixture of BPA/DC, l,l,l-tris(4-cyanatophenyl)ethane, nonylphenol and Zn naphthenate [21]. The cross-linked polymer from BPA/DC, maleic anhydride, p-toluenesulfonic acid, Zn acetate and DABCO has high Tg [22]. BPA/DC monomer can be replaced by the corresponding prepolymer with p-toluenesulfonic acid monohydrate and Zn acetate. The composition obtained is processed as a molding compound [23],... 

Polystyrene modified dicyanate polymer was obtained by simultaneous polymerization of styrene monomer and BPA/DC. The handling of low viscous dicyanate solution in styrene is more convenient that the processing of crystalline BPA/DC or high-viscous dicyanate prepolymers [52]. A similar patent specification describes the polymerization of a mixture of styrene, BPA/DC and p-isopropenyl cyanate BMI (cf. Sect. 5) was also used [53]. 

Acrylic monomers glycidyl methacrylate together with an epoxide resin [54], 2-hydroxyethyl methacrylate [55] and 2-ethylhexyl acrylate [56] containing dissolved BPA/DC were heated to obtained prepolymers, which were further polymerized a peroxide initiator or UV irradiation was applied. 

Heating of a mixture of BPA/DC and BMI at 100-160 °C results in a formation of prepolymers, known as BT Resins of Mitsubishi Gas Chemical Co. [57]. A broad assortment of BT Resins has been developed. Some of the BT Resins are modified with epoxide resins, unsaturated monomers etc. 

Instead of BPA/DC monomer, the corresponding prepolymer was heated with BMI to obtain a binder [62], In a similar composition, p-toluenesulfonic acid was used as the cyanate/maleimide prereaction catalyst. For the crosslinking stage Zn octoate was added [63], Both BPA/DC and BMI can be used in the form of prepolymers. The binder for copper clad laminates contains, moreover, a saturated polyester, Zn octoate and powdered fused quartz [64],... 

Fire resistant reinforced plastic was obtained by using tetrabromo-BPA based epoxide resin, BPA/DC monomer and prepolymer as well as an imidazole curing agent and Zn octoate [82],... 

A binder for copper clad laminates contains the prepolymer from BPA/DC and A -(3,5-dimethyl-4-vinylphenyl)maleimide in methylethylketone, an epoxynovolak resin, Zn acetate and tert.butyl peroxide [100], In a similar composition, a prepolymer obtained from epoxide resin, BMI and bis(4-aminophenyl)methane was mixed with BPA/DC, Zn acetate and tert.butyl peroxide in solution [101]. 

Epoxynovolak resin and BPA/DC-BMI prepolymer, tert.butyl peroxide and Zn acetate [106, 107] or 2-phenylimidazole and other catalysts [108] were filled with wollastonite. Carbon-fiber reinforced composites were obtained using a binder, which consisted of BPA/DC, BMI, an epoxynovolak, 2-ethyl-4-methylimidazole and an organic solvent [109]. A BPA/DC-BMI prepolymer in methylethylketone was mixed with middle-molecular-weight epoxide resin (Epikote 1001), 2-ethyl-4-methyl-imidazole, Zn acetate and triethylenediamine thermal shock resistant GRP was thus obtained [110]. 

As in the cyanate/epoxide compositions, polysulfone is used as an additive in cyanate/epoxide/maleimide systems. As an example, a composition for carbon-fiber composites should be mentioned. It contains BPA/DC-BMI prepolymer, epoxide resin and polyethersulfone [111-113] Zn acetate and dicumyl peroxide are added. Polyethersulfone powder was added to the three-component system with 4,4 -diamino-diphenylmethane-based tetraepoxide as one of the epoxy resins used [114]. 

A coating composition consists of BPA/DC-BMI prepolymer, epoxide resin and Zn acetate in dimethylformamide a solution of polyhydantoin in CH2C12 is added [121]. 

An electroinsulating coating was obtained by mixing a polyimide resin with BPA/ DC or BPA/DC-BMI prepolymer. The low-molecular-weight polyimide resin contained reactive end groups (—C = CH, COOH, —NH2 etc.) [140]. 

Binders for copper clad laminates consist of a solution of phenolic resol (part A) and of a composition obtained from a drying oil modified resol, hexamethylene-tetraamine and BPA/DC monomer or prepolymer [142, 143]. 

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