ORGANIC CHEMISTRY MASTERINGCHEM ACCESS
9th Edition
ISBN: 9780137249442
Author: Wade
Publisher: INTER PEAR
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Chapter 26, Problem 26.34SP
Interpretation Introduction
Interpretation: The mechanism for the formation of urea formaldehyde resin by showing the base catalyzed condensation of urea with formaldehyde is to be proposed.
Concept Introduction: Urea reacts with formaldehyde in the presence of ammonia as a catalyst to form urea formaldehyde resin. This
To determine: The mechanism for the formation of urea formaldehyde resin.
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Plywood and particle board are often glued with cheap, waterproof urea-formaldehyde resins. Two to three moles of formaldehyde are mixed with one mole of urea and a little ammonia as a basic catalyst. The reaction is allowed to proceed until the mixture becomes syrupy, and then it is applied to the wood surface. The wood surfaces are held together under heat and pressure, while polymerization continues and cross-linking takes place. Propose a mechanism for the base-catalyzed condensation of urea with formaldehyde to give a linear polymer, and then show how further condensation leads to cross-linking.
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Chapter 26 Solutions
ORGANIC CHEMISTRY MASTERINGCHEM ACCESS
Ch. 26.2A - Show the intermediate that would result if the...Ch. 26.2A - Prob. 26.2PCh. 26.2A - Prob. 26.3PCh. 26.2B - Prob. 26.4PCh. 26.2B - Prob. 26.5PCh. 26.2B - Chain branching occurs in cationic polymerization...Ch. 26.2C - Prob. 26.7PCh. 26.2C - Prob. 26.8PCh. 26.2C - Chain branching is not as common with anionic...Ch. 26.3 - Prob. 26.10P
Ch. 26.5 - Prob. 26.11PCh. 26.6 - Prob. 26.12PCh. 26.7A - Prob. 26.13PCh. 26.7B - Prob. 26.14PCh. 26.7B - Prob. 26.15PCh. 26.7C - a. Propose a mechanism for the reaction of...Ch. 26.7C - Prob. 26.17PCh. 26.7D - Prob. 26.18PCh. 26.7D - Prob. 26.19PCh. 26.7D - Prob. 26.20PCh. 26 - Prob. 26.21SPCh. 26 - Prob. 26.22SPCh. 26 - Poly(trimethylene carbamate) is used in...Ch. 26 - Prob. 26.24SPCh. 26 - Urylon fibers are used in premium fishing nets...Ch. 26 - Prob. 26.26SPCh. 26 - Prob. 26.27SPCh. 26 - Polyoxymethylene (polyformaldehyde) is the tough,...Ch. 26 - Prob. 26.29SPCh. 26 - Prob. 26.30SPCh. 26 - Prob. 26.31SPCh. 26 - Prob. 26.32SPCh. 26 - Prob. 26.33SPCh. 26 - Prob. 26.34SPCh. 26 - The polyester named Lactomer is an alternating...Ch. 26 - Prob. 26.36SP
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