Ammonia from poly amidation

Usual attachment of the first amino acid unit to the chloromethylated poly-styrene-divinylbenzene resin has been improved, for example, with Boc-Asn, by-condensing the amino acid (2.0 mmoles) in DMF with triethylamine (1.8 mmoles) during one day at room temperature. Cleavage of the peptide end product from the polymer as the amide derivative has been accomplished using ammonia in DMF in a sealed reaction vessel at room temperature for 5 days. A careful stud - of several peptide bond-forming reagents and polymer supports in respect to racemization has revealed the DCCI procedure to be far inferior to DCCI-NHS or EEDQ. With the model tripeptide Gly-Ala-Leu (racemization assessment by means of the Izumiya procedure), the product was found to... 

If a blend of poly(methyl methacrylate) and polyacrylonitrile is thermally degraded, the behaviour of the poly (methyl methacrylate) is profoundly affected, but that of the polyacrylonitrile is unaltered. The methacrylate units react with ammonia arising from the polyacrylonitrile, and the amide-ester copolymer so formed undergoes complex degradation reactions, rather than the depolymerization to monomer which takes place with unchanged poly(methyl methacrylate). 

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