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The resin manufacturing parameters which need to be manipulated to produce urea-formaldehyde (UF) resins capable of producing low formaldehyde emission particleboards of class E l are presented and discussed. Several E l UF resin formulations are presented and discussed, each achieving the wanted goals of strength and low formaldehyde emission by different approaches but still satisfying the required balance of preparation parameters. The different approaches were explained on the basis of the relative proportions of the chemical species produced analyzed by 13 C NMR. Resins preparation and structural parameters and relative proportions of the chemical species present in the final resin were compared and related. Both the manufacturing procedures and the laboratory and industrial boards results produced using these formulations are presented, underlying a common denominator in all these types of formulations. At laboratory level even formulations of urea : formaldehyde molar ratio äs low äs 1.: 0.7 gave an acceptable balance of results, while industrially the Optimum balance of properties appeared to be reached in the molar ratio ränge of l : 0.9 to l : 1.0 but particularly at around l : 0.96. El emission levels of 5 mg/100 g board and lower (by perforator test) were achieved with ease.

Application to the manufacture of marine and exterior-grade plywood of the novel reactions and mechanisms of diisocyanates and formaldehyde-based resins already described, is reported. Plywood adhesives capable of producing excellent marine-grade bonds on difficult-to-bond wood species, normally unbondable with PFresins, at both laboratory and industrial levels are reported. Other remarkable characteristics of these resins were shown to be their tolerance to higher moisture content of the veneers, their ease of handling, preparation and assembly as well as, being water-based systems, their ease of cleaning in an industrial environment. The theory underlying the preparation of optimal phenolrformaldehyde (PF) resins for reaction in water with diisocyanates, and how to adapt these mixed adhesive systems to different types of PF resins, is also presented. Formulations, glue-mixes and results from successful industrial trials are reported in detail.

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The present research seeks to study the quality of the pyrolytic liquids obtained from the catalytic pyrolysis of plastic waste. Samples obtained at four temperature conditions-550 ° C, 600 ° C, 650 ° C and 700 ° C-and three were analyzed With the catalyst / plastic residue ratio conditions-0, 10 and 20%-, the following physicochemical properties were evaluated: pour point (ASTM D97), kinematic viscosity (ASTM D445) and Pensky Martens flash point (ASTM D93). The results obtained show that the higher the catalyst / plastic residue ratio, the lower the pour point. Regarding the viscosity, the higher catalyst / plastic residue ratio and for the same temperature, the viscosity decreases. In the case of the Pensky Martens flash point, the higher the catalyst / plastic residue ratio, the lower the flash point. It is concluded that the liquid product obtained does not meet the national specification of Diesel B5, but it resembles a Talara crude.