Incorporation dicyclopentadiene

Levels of cyclopentadiene (CPD) and dicyclopentadiene (DCPD) in C-5 feedstreams have a great effect on the softening point, as well as the color and thermal stabiUty of the resin. Typically, DCPD is added to C-5 feedblends to increase softening point. However, increased DCPD incorporation... 

Other Reactants. Other reactants are used in smaller amounts to provide phenoHc resins that have specific properties, especially coatings appHcations. Aniline had been incorporated into both resoles and novolaks but this practice has been generally discontinued because of the toxicity of aromatic amines. Other materials include rosin (abietic acid), dicyclopentadiene, unsaturated oils such as tung oil and linseed oil, and polyvalent cations for cross-linking. 

Ethylene—Propylene Rubber. Ethylene and propjiene copolymerize to produce a wide range of elastomeric and thermoplastic products. Often a third monomer such dicyclopentadiene, hexadiene, or ethylene norbomene is incorporated at 2—12% into the polymer backbone and leads to the designation ethylene—propylene—diene monomer (EPDM) mbber (see Elastomers, synthetic-ethylene-propylene-diene rubber). The third monomer introduces sites of unsaturation that allow vulcanization by conventional sulfur cures. At high levels of third monomer it is possible to achieve cure rates that are equivalent to conventional mbbers such as SBR and PBD. Ethylene—propylene mbber (EPR) requires peroxide vulcanization. 

To synthesize new surfactants, having incorporated both structural elements, the known siloxanyl modified halogenated esters and ethers of dicyclopentadiene [5] were treated with different amines according to the reaction scheme. Triethylamine yielded quaternary ammonium salts directly. Alternatively, after reaction with diethylamine or morpholine, the isolated siloxanyl-modified tertiary amines were also converted to quaternary species. To obtain anionic surfactants, the halogenated precursors were initially reacted with n-propylamine. In subsequent reaction steps the secondary amines formed were converted with maleic anhydride into amides, and the remaining acid functions neutralized. Course and rate of each single reaction strongly depended on the structure of the initial ester or ether compound and the amine applied. The basicity of the latter played a less important role [6]. 

Figure 8. Incorporation of dicyclopentadiene in EPDMS. Key A, V ss-Et,A 2Cls-ETCA B, Vs 0-EtsAhCl3, Et2AlCl or Et,AI2CI2/Et2AICI (1 1) C, V(acac),-...

The rationale in using these particular dienes is that only the strained double bond of dicyclopentadiene and the terminal double bond of 1,4-hexadiene undergo polymerization with Ziegler catalysts. Consequently the polymer chains contain one double bond for each molecule of dicyclopentadiene or 1,4-hexadiene that is incorporated. These double bonds later can be converted to cross-links by vulcanization with sulfur (Sections 13-4 and 29-3). 

During the last years ROMP has been developed to generate self-healing polymers. In these polymers droplets of dicyclopentadiene and of Grubbs-catalyst are incorporated. When the polymer cracks the droplets burst open, the catalyst comes into contact with the monomer and the plastic ideally heals itself [111]. This methodology is still far from application but it does indicate the power of ROMP. 

Copolymerization of ethylene with propylene results in a random, noncrystalline copolymer that is a chemically inert and rubbery material. EPM is a saturated copolymer that can be cross-linked through the combination of the free radicals generated by peroxides or radiation. To incorporate sites for vulcanization, an unsaturated terpolymer can be prepared from ethylene, propylene, and a small amount (3 to 9%) of a nonconjugated diene (EPDM). The diene is either dicyclopentadiene, ethylidene nor-bomene, or 1,4-hexadiene. The resulting unsaturated terpolymer can be vulcanized by traditional techniques. Each of the termonomers confers different characteristics on the final elastomer. 

PGC has been used to determine the overall composition of ethylene-propylene-diene terpolymers [10]. In attempting to determine the third component in these materials, difficulties might be anticipated, since this component is normally present in amounts around 5 wt%. However, dicyclopentadiene was identified in ethylene-propylene-diene terpolymers even when the amount incorporated was very low. 

Van Schooten and Evenhuis [86, 87] applied their pyrolysis (500 °C)-hydrogenation-gas chromatography technique to unsaturated ethylene-propylene copolymers, i.e., ethylene-propylene-dicyclopentadiene and ethylene-propylene-norbornene terpolymers. The pyrograms show that very large cyclic peaks are obtained from unsaturated rings methylcyclopentane is found when methylnorbornadiene is incorporated cyclopentane when dicyclopentadiene is incorporated methylcyclohexane and 1,2-dimethylcyclohexane when the addition compounds of norbornadiene with isoprene and... 

Using NRs, White and coworkers developed self-repaired polymers. This approach was based on incorporation of microcapsules loaded with healing agents, dicyclopentadiene monomers, and using a proper catalyst in epoxy matrix. Formation of cracks ruptured the microcapsules and released healing... 

A different system for chelating at Ru, i.e. a bidentate carbene-pyridine, was devised by Van der Schaaf et al. , the resulting catalyst being used in polymerization of dicyclopentadiene (DCPD) the idea was extended by Grubbs et al. to yield the second-generation catalyst 35. Fiirsmer et aL incorporated a coordinating carbonyl ester on the bidentate carbene and... 

The literature describes several cases of the copolymerization of ethylene with cyclopentene [31b], cyclo-heptene [31b], norbornene [31c], 2-methylnorbornene [31c], dicyclopentadiene [31d], dimethanooctahydro-naphthalene [31a,e], and 2-methyldimethanooctahy-dronaphthalene [31a]. When chiral catalysts were employed (e.g., ethylenebis(indenyl)zirconium dichloride associated with methylaluminoxane), the activity was much higher than that of the achiral catalyst. In addition, the ehiral catalyst increased the polymer stereoselectivity and the amount of the cycloolefin incorporated into the copolymer. Materials having exeellent transpareney, thermal stability, and ehemical resistance—properties that are useful for optical disks—may be produced efficiently by this method. 

The incorporation of rapeseed oil improved the mechanical properties which depend on flexibiUzation tensile, flexural and impact strength and elongation at break as well. Dicyclopentadiene increased the flexural and compression strength, hardness and heat deflection temperature (HDT) and the chemical resistance, which is, in general, better in water and in aqueous solutions of acids than in alkali (10% KOH). 

Epoxy vinyl ester, phenolic, methacrylate, styrene-divinylbenzene, cyanafe ester, and dicyclopentadiene (DCPD) resins have been made in Pittman s laboratory in which various POSS macromers have been chemically incorporated. For example, a low-viscosity aliphatic epoxide resin was blended with macromer 32 (Fig. 15) and aliphatic triamine curing agents, and these blends were cured in five stages to both 120°C and 150°C. The incorporation of 5 and 25 wt % of 32 into these epoxy resins gave an increase in the storage modulus versus that of the neat epoxy. " The... 

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