Thermally-reversible isocyanate polymers

The melt-processable polymer composition of claim wherein said isocyanate-labile hydrogen backbone linkage is bonded to an aryl and an alkyl group.

A process for forming a melt-processable polymer composition comprising reacting a first compound with isocyanate functionality with a second compound with labile-hydrogen functionality to yield a polymer with a isocyanate-labile hydrogen backbone linkage that reversibly dissociates at above about 150.degree. C. into said compounds with isocyanate and labile-hydrogen functionality and has a viscosity less than about 100,000 poise.

A process for preparing a melt-processable polymer composition comprising:

• a. melting and mixing a high-melting compound with labile-hydrogen functionality with a low-melting compound with labile-hydrogen functionality to form a homogenous melt and
• b. adding to said homogeneous melt a compound with isocyanate functionality to yield a polymer with an isocyanate-labile hydrogen backbone linkage that reversibly dissociates at above about 150.degree. C. into said compounds with isocyanate and labile-hydrogen functionality and a viscosity less than about 100,000 poise.

A polyester oligomer comprising a compound represented by the acronym sequence PH-[DHA-DAH].sub.n -DHA-PH were PH is a phenolic hydroxy acid ester segment, DHA is a difunctional segments selected from the group of difunctional segments consisting of aromatic diacid ester, aromatic dihydroxy, aromatic hydroxy and acid ester, aliphatic diacid ester, aliphatic dihydroxy, and aliphatic hydroxy and acid ester segments, DAH is selected from the group of difunctional aromatic segments consiting of aromatic diacid ester, dihydroxy, and acid ester and hydroxy segments with DAH and DHA being choosen so as to form an ester group, with PH being chosen to form an ester with the terminal group of the DHA-DAH sequence and n is about 1-20.

A polyimide oligomer comprising a compound represented by the acronym sequence AP[DA/DAm].sub.n DA/AP where AP is an aromatic amine phenol endcapper, DA is an aromatic dianhydride selected from the group of aromatic dianhydrides consisting of fused and unfused aromatic ring dianhydrides, and DAm is a diamine coupler selected from the group of aromatic diamines and aliphatic diamines and wherein each of the amine groups of DAm is linked to one of the anhydride group of a distinct dianhydride DA as an imide, the amine of the phenol endapper (AP) is linked to the end unit anhydride group of the dianhydride as an imide and n is about 1-20.

A polycarbonate oligomer comprising a compound represented by the acronym sequence DP1-C-[DP2-C].sub.n DP1 where DP1 is an aromatic diphenol, C is carbonate functionality, DP2 is selected from the group of diphenols consisting of aromatic diphenols that may be the same as DP1 and aromatic-aliphatic diphenols and wherein C is carbonate functionality derived from a carbonyl and the oxygen moiety on seperate phenol units and n is about 1-20.