Epoxy-Cresol-Novolac ECN Resins

One of the major uses of ortho-cresol is for manufacture of epoxy-cresol-novolac (ECN) resins CAS No. [37382-79-9]. The acidic reaction of less than an equimolar concentration of formaldehyde with o-cresol yields cresol-novolac resins. 

The epoxy-cresol—novolaks resins are prepared by glyci-dylation of o-cresol-formaldehyde condensates in the same manner as phenol-novolak resins, o-cresol-formaldehyde condensates are prepared under acidic conditions with HCHO-o-cresol ratios of less than unity. The o-cresol novolacs of commercial significance possesses degrees of polymerization, n, of 1.7-4.4 and the epoxide functionality of the resultant glycidylated resins varies from 2.7 to 5.4. Softening points (Durrain s) of the products are 35-99°C [31]. 

The ECN resins are multifunctional, solid polymers characterized by low ionic and hydrolyzable chlorine impurities, high chemical resistance, and good thermal performance. The ECN resins are widely used as base components in high-performance electronic and structural molding compounds, micro-chip encapsulation, high—temperature adhesives, structural molding powders, etc. 

DOW is the largest US producer of ECNs with its new 10 million pounds (4500 tpa) capacity plant in Freeport, TX. Other producers of ECNs include Ciba-Geigy, Border Chemicals, Shell and Schenectady Chemicals [6]. 

The worldwide market for ECNs approximately total 30 million pounds (13,640 tpa). USA exports more than 50% of its production to W. Europe and Asia. The major producers of ECN resins in W. Europe are Ciba-Geigy, EMS-Chemie Ag, and Hoechst. Approximately 1500—2000 tpa of ECNs are produced in W. Europe [6]. 

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See also Epoxy coatings Epoxy chalcone, 10 450 12,13-Epoxy-cis-9-octadecenoic (vernolic) acid, physical properties, 5 35t Epoxy coatings, 10 436 450 17 845. See also Epoxy can coatings for corrosion protection, 7 199 markets for, 10 442-449 performance of, 10 423 waterborne, 10 439 Epoxy composites, 10 450, 451 Epoxy compounds, photoinitiated polymerization of, 23 716 Epoxy content analysis, 10 385 Epoxy cresol novolac (ECN) resins, 10 367, 369... 

Others include brominated bisphenol A resins which impart fire resistance, epoxy phenol novolac (EPN) resins, bisphenol F epoxy (DGEBF) resins, epoxy cresol novolac (ECN) resins, cycloaliphatic epoxy resins, and tetraglycidyl-4,4 -diaminodiphenylmethane (TGDDM). 

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