Caprolactam based block copolymers using polymeric activators

Abstract

Caprolactam has been polymerised by sodium hydride in the presence of isocyanate terminated polymers. The latter participate in the initiation reaction and allow the preparation of materials where the prepolymer can amount to 50% of the product.There is evidence that block copolymers are formed, and the properties of polycaprolactam are considerably modified by the use of such activators. Styrene-butadiene or, particularly, caprolactone based isocyanates give materials having properties similar to the harder thermoplastic polyurethanes. The dependence of properties on the nature and amount of the polymeric activators, and the conditions of preparation and processing, have been investigated. Crystalline morphology has also been examined. Tensile strengths of 50 MN/m2 with 550% elongation at break are readily attainable with these materials. ZUSAMMENFASSUNG:Caprolactam wurde, initiiert durch Natriumhydrid, in Gegenwart von Polymeren mit Isocyanatendgruppen polymerisiert. Die Endgruppen nehmen an der Startreaktion teil und ermoglichen die Herstellung von Materialien, die bis zu 50% des Prepolymeren enthalten.Dabei entstehen Blockcopolymere; die Eigenschaften von Polycaprolactam werden durch solche polymere Aktivatoren betrachtlich modifiziert. Aus Styrol-Butadien oder besonders aus Caprolacton aufgebaute Isocyanate ergeben Materialien mit ahnlichen Eigenschaften wie die harteren thermoplastischen Polyurethane. Die Abhangigkeit der Eigenschaften von Art und Menge des polymeren Aktivators und von den Herstellungsbedingungen wurde untersucht. Ferner wurde die Kristallitmorphologie untersucht. Zugfestigkeiten von 50 MN/mZ bei 550% Bruchdehnung werden bei diesen Materialien erreicht.

Polymerization of lactams, 95 Preparation of polyesteramides by the anionic polymerization of ε-caprolactam in the presence of poly(ε-caprolactone)

“…[12] show distinctly higher elongation, as compared to those of ours. Undoubtedly, the system CLA/PCLO (CLO)/-CLAMgBr/N-acyllactam is suitable for the polymerization casting; in contrast, preparation of the material according to a published procedure [12] does not yield a good-quality plastics.…”

“…Allen and Eaves [12] reported on polyesteramides prepared by NaH-initiated anionic polymerization of CLA in the presence of isocyanato-terminated PCLO ðM n , 2000 g mol 21 Þ: Comparing properties of these copolymers with those described in the present paper, we find that the use of CLAMgBr gives always higher yields of the polymer, approaching the equilibrium content of CLA achieved during the preparation of PCLA. Materials according to Ref.…”

Tri-block copolymers with mono-disperse crystallizable diamide segments: Synthesis, analysis and rheological properties

“…These SBS tri-block copolymers usually demonstrate low moduli and low maximum use temperatures. Tri-block copolymers with crystallizable end segments have been made from short soft mid-segments (600-3000 g/mol) and long nylon-6 or nylon-11 hard segments [3,4]. The long nylon blocks were phase separated from the soft segments and the nylon blocks were partly crystalline.…”

Synthesis of nylon-6 triblock copolymers with bifunctional polymeric activators

“…In the literature, there are reported elastomeric blocks based on different polyethers [polyethyleneoxide, polypropyleneoxide, and polytetrahydrofuran (PTHF)], [1][2][3][4][5] polybutadiene, [6][7][8] butadiene-acrylonitryl copolymer diols, 9 styrene-butadiene, 10 and polyethersulfone. 11 In addition, a commercial multiblock copolymer (PEBAX) based on polyamide and PTHF prepared by polycondensation is well known.…”