Crosslinking coagent

Uses Coactivator, crosslinker, coagent for wire and cable, hard rubber rolls, polybutadiene, polyethylene, moisture barrier films and coatings, plastisols and vinyl acetate latexes, adhesives, molding compds., textile prods. comonomer for polymerizable/softened PVC plastisols reactive diluent for radiation-cured inks/lacquers processing aid for extrusion and molding of plastisols and rubber compds. Improves scorch resist. 

Keywords crosslinking, crosslinking mechanism, crosslinking coagent, macroradical, peroxide initiation, irradiation, degradation, controlled rheology PP, foams, compatibilization. 

The goal was to obtain an elastomeric composites with both increased mechanical, thermal properties and a certain time of degradation. Modified ionic liquids fillers behaved like crosslinking coagents during peroxide curing and as a result increased the crossling density of vulcanisates. Moreover they influenced on the dispersion of filler in elastomeric matrix what led to increase of mechanical properties. 

The saturated main chain of the copolymer confers excellent resistance to oxygen, ozone and light, but means that these materials cannot be crosslinked by sulphur. Peroxides and radiation are the only methods by which crosslinking can be accomplished, and coagents are often required to achieve the required state of cure. 

Crosslinking systems based on peroxides are usually simple. Unlike with sulphur vulcanisation systems, the addition of ZnO and stearic acid is not necessary, so crosslinking is achieved in many cases simply using a crosslinking peroxide. However, the addition of a coagent may be useful (see below). In some other cases, a combination of various types of crosslinking peroxides may be suitable. 

The coagent functionality of this compound helps to improve the crosslinking effect, and is comparable with DCP. Moreover, the multifunctional peroxides investigated provide by-products after their decomposition, but without an unpleasant smell, unlike DCP. Comparative physical properties of the PP/EPDM TPVs... 

The competition between the phase separation and crosslinking processes opens up the possibility of controlling pattern formation and the structure of the resulting material by varying the reaction temperature and the blend composition. There is considerable effort to modify the useful properties of elastomers by introducing a coagent that is copolymerized with the elastomer and contributes positively... 

Apart from the effect on the crosslinking efficiency, the use of co-agents in peroxidecuring also imparts the molecular structure of crosslinks. It has been reported that coagents with two or more unsaturated moieties can be incorporated as individual molecules between two elastomer strands to form crosslinks [103-109]. In this way the crosslink structure of peroxide-cured elastomers can be altered. Thus, apart from the expected benefits, such as improved crosslinking efficiency, decreased compound viscosity and faster cure, the use of co-agents may also provide a tool for manipulating mechanical properties. 

Acrylic acid, zinc salt Ageflex ZDA EINECS 238-692-3 2-Propenoic acid, zinc salt Zinc acrylate Zinc dlacrylate. Crosslinker for molded polybutadiene compounds, conductive and protective coatings, coagent for SBR compounds and reactive pigments activator for rubber compounding scorch retarder. Rit-Chem. 

In another study, the monoacrylate 35 was grafted onto PP in the presence of tris(acryIoyhnethyl)propane (36) as coagent.Again close to 100% grafting yield was obtained. This was so despite the fact that 35 was anticipated to be an inhibitor of free radical reactions (in fact, phenols are poor inhibitors of (meth)acrylate polymerization - Section 5.3.4). The tris-acrylatc 36 and related species have previously been used for producing crosslinked/branched xhe structure... 

If butadiene is used as a coagent, the dose for gel formation is reduced by a factor 5 [77]. It is of interest that parallel to an increase of radiation yield of crosslinking, the yield of chain sdssions inoeases, as well. For instance, for butadiene, G of cross-linking is 0.69 andG of sdsdtms isO.44 for divinyl sulphone (CH, = CHSO CH=CHj) this value is 0.46 and 1.1, respectively. From the G value it may thus be seen that the... 

Uses Resin for wire coating, EPDM peroxide-cured modifier, coatings processing aid crosslinking agenL coagent for rubber modifier for rubber, plastics, mastics, adhesives oil well cables heat-resist, rubber Features Thermosetting... 

Properties Liq. insol. in water m.w. 226.28 dens. 1.010 b.p. 290 C flash pt. (COC) 124 C ref. index 1.4520 Toxicology TSCA listed Storage Light-sensitive Uses Peroxide crosslinker/coactivator for elastomers, PVC plastisols, syn. resins, cast acrylic sheet/rods coagent for rubber compding. impregnant for metal and wood composites, adhesives, and glass-reinforced... 

CAS 13189-00-9 EINECS/ELINCS 236-144-8 Synonyms Methacrylic acid, zinc salt 2-Methylacrylic acid zinc salt 2-Propenoic acid, 2-methyl-, zinc salt ZDMA Zinc dimethacrylate Zinc 2-methyl-2-propenoate Classification Nonaromatic acid salt Empirical CsHio04Zn Properties M.w. 235.54 m.p. 229-232 C Toxicology Irritating to eyes, skin, respiratory system sensitizer TSCA listed Uses Coagent, scorch retarder, crosslinking agent for elastomer processing and cure polymer modifier... 

Crosslinking can sometimes be increased by the use of bifunctional triallylisocyanurate TAIC the level of peroxide required is then lower. TAIC is then called a coagent. 

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