Rubbers crosslinking agents

Uses Adhesion promoter in adhesives primer or adhesive additive for adhering elastomeric coatings to syn. fiber fabrics coated with syn. rubbers crosslinking agent for elastomers and plastics Features No ozone-depleting substances Properties Dk. brn. liq. mod. sol. in alcohol, toluene, chloroform si. sol. in petrol, ether pract. insol. in water dens. 1.24 0.02 mg/m flash pt. (PM) 30 C min. 16.8% isocyanate content Toxicology TSCA listed Vanchem HM-4346 [R.T. Vanderbilt]... 

HMIS Health 3, Flammability 1, Reactivity 1 Uses Coupling agent for epoxies, phenolics, melamines, nylons, PVC, acrylics, urethanes, nitrile rubbers crosslinking agent adhesion promoter for coatings in food-pkg. adhesives Regulatay FDA 21CFR 175.105... 

Precaution Flamm. reactive with active metals Hazardous Decomp. Prods. Heated to decomp., emits very toxic fumes of Cl and NOx Uses Curing agent for polymers hardener for plastics and rubber crosslinking agent for PU Regulatory HAP Manuf./Distrib. Allchem Ind. http //WWW. aiichem. com... 

Uses Bonding uncured rubber to metal or other surfaces diene rubber crosslinking agent PU boot/shoe adhesives... 

Film Nitrile rubber Crosslinking agent One-step BKR -2620 SP -8014... 

Film Nitrile rubber Crosslinking agent Two-step BKPA -5864 Durez 12687... 

The original compound, maleimide (2,5-dioxo-A -pyrroline), is synthesized by the cyclo-condensation of ammonia and maleic acid. Similarly, primary amine is added to maleic anhydride, followed by cyclocondensation, to form N-substituted maleimide (Fig. 2). This reaction is applied to the preparation of bis-maleimides (BMl) [1]. At first, BMI was used as a crosslinking agent for natural rubber (NR). An o-dichlorobenzene solution of NR was crosslinked by BMI at I08-150°C in the presence of peroxides. The radicals generated from peroxides react with the double bonds of both BMI and NR [ 1 ]. 

Modified PAN fibres have been obtained from copolymers containing up to 15% or ISP units using the wet spinning process30. Some properties of modified fibres are presented in Table 1. For comparison are also given the properties of fibres obtained from copolymers additionally crosslinked with conventional crosslinking agents used in the vulcanization of nitrile rubbers. 

Substituted phenols such as cresols, p-fcrf-butylphenol, / -phcnylphenol, resorcinol, and cardanol (derived from cashew nut shells) have also been used as precursors for phenolic resins. Alkylphenols with at least three carbons in the substituent lead to more hydrophobic phenolic resins that are compatible with many oils, natural resins, and rubbers.7 Such alkylphenolic resins are used as modifying and crosslinking agents for oil varnishes, as coatings and printing inks, and as antioxidants and stabilizers. Bisphenol-A (2,2-p-hydroxyphenylpropane),... 

Foly(dimethylsiloxane) (silicone rubber) membranes are fabricated by hydrolysis of alkox-ysilyl terminal groups of silicone-rubber precursors [oligo(dimethylsiloxane) derivatives and crosslinking agents], followed by condensation. Covalent bonding of neutral carriers carrying an alkoxysilyl group to silicone rubber is, therefore, feasible by simple reaction of the silicone-rubber precursor with alkoxysilylated neutral carriers, as schematically shown in Scheme 1 [44]. 

The first modern day negative photoresists were developed by the Eastman Kodak Company which utilized cyclized rubbers and cinnamic acid derivatives as photosensitive crosslinking agents (42). The first commercially important photoresist based on this chemistry was known as KPR, which was of a cinnamate ester of polyvinyl alcohol. It was introduced by Kodak in 1954. 

Nano-powdered styrene/butadiene rubber has been synthesized by the radiation crosslinking of styrene-butadiene rubber (SBR). Tri-methylolpropane triacrylate can be used as crosslinking agent. This monomer improves the radiation crosslinking of the SBR latex. 

Figure 10.4 Mesh size distributions in a natural rubber sample filled with carbon black and containing a gradient of crosslinking agent. Data were obtained with n-heptane.

Chemical interaction between furnace blacks and rubbers is responsible for the greater extent of reinforcement for polar rubbers [153]. Lately, it has been reported that -OH and -COOH groups of surface oxidised furnace blacks react chemically with functionalised polymers like CSM [154], XNBR [155] and ENR [156], forming a crosslinked vulcanisate in the absence of any crosslinking agent. The mechanism of chemical interactions is supported by IR spectroscopy. 

W.C. Endstra, Rubber Chemicals, Application Research Bulletin, Crosslinking Agents, Akzo Nobel, 1985. 

PVC can be chlorinated (CPVC) and be alloyed with other polymers like ABS, acrylics, polyurethanes, and nitrile rubbers to improve its impact resistance, heat deflection, and processability. Although these vinyls differ in having literally thousands of varying compositions and properties, there are certain general characteristics that are common to nearly all these plastics. Most materials based on vinyls are inherently TP and heat sealable. The exceptions are the products that have been purposely compounded with TSs or crosslinking agents are used. 

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