Polyspirodilactam: A new family of high temperature polymers

Abstract

A new class of materials based on a spirodilactam structure has been recently synthesized as part of research into new polymeric materials. Not only is the spirodilactam structure novel, but it was not even the intended product in the synthesis as originally designed. The polymerization process discovered by the reaction of 4‐ketopimelic acid or its corresponding spirodilactone with primary amines opened a new field of polysprodilactam chemistry. This paper describes the chemistry leading to the discovery of spirodilactam‐based polymers and initial applications in the area of thermoplastics and thermosets. Most recent developments to be covered include aromatic spirodilactams and isomeric spirodilactams.

Synthesis of Long-Subchain Hyperbranched Polypropylene Using Thermally Degraded Products as Precursor

“…Basically, linear PP takes the form of an α crystal, while LHB-PPs contains both α and γ crystals. The γ phase in linear PP is observed as a minor constituent in the bulk crystallization of PP at atmospheric pressure, which is difficult to be seen in linear PP , (Figure ). The formation of γ crystals is closely related to the molecular chain structure, including the content and distribution of defects, the relative molecular weight, and the content and distribution of the comonomer.…”

“…The formation of γ crystals is closely related to the molecular chain structure, including the content and distribution of defects, the relative molecular weight, and the content and distribution of the comonomer. In general, the change in relative content of the γ crystal can be attributed to the average identical sequence length (identical sequence lengths between two defects) of PP . In this case, the LHB-PPs have a relatively shorter identical sequence ( M w = 18k, HT-GPC-LS) between two branched points, which can easily induce the formation of γ crystals.…”

“…In general, the change in relative content of the γ crystal can be attributed to the average identical sequence length (identical sequence lengths between two defects) of PP. 42 In this case, the LHB-PPs have a relatively shorter identical sequence (M w = 18k, HT-GPC-LS) between two branched points, which can easily induce the formation of γ crystals.…”

Sulfuric acid and Amberlyst-H+ catalyzed condensation reactions of renewable keto acids with paraformaldehyde: synthesis of a new dispiro bis-lactone ring system 2,9,13-trioxadispiro[4.1.4.3]tetradecane-3,6,10-trione

“…34 Missio et al have used 4-KPA as the key starting compound for the enantioselective synthesis of (À)-gjasmolactone, 35 and in a few occasions the diacid has been used directly as a monomer in polymer synthesis. [36][37][38][39][40][41] Based on the experience from LA-PF study, we have used ve equivalents of PF in the 4-KPA-PF experiments, leaving one extra equivalent than the required four equivalents for complete hydroxymethylation of both a-carbons at the keto group. The optimum reaction conditions were found to be heating a mixture of 4-KPA and PF in 1 : 5 mole ratio for 24 h at 80 C, with 20 mol% conc.…”

New spirodilactam polymers

“…A new class of monomers containing the rigid 1,6-diazaspiro [4.4]nonane-2,7-dione (spirodilactam) core structure has recently been described [1]. Polymers containing this spirodilactam structure in the backbone generally have good thermal stability with relatively high glass-transition temperatures as well.…”