Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – From reactant having at least one -n=c=x group as well as...
Patent
1999-05-18
2000-10-31
Gorr, Rachel
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
From reactant having at least one -n=c=x group as well as...
528354, 25218227, 525533, 560189, C08G 1848
Patent
active
061404535
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTION
The invention relates to a thermoplastic polyurethane material of general formula I: ##STR4## where f is an integer ranging from 1 to 500; f is an integer ranging from 1 to 15; R and R' are the same or different and stand for alkyl or aryl groups and X is a polyether-polycaprolactone block copolymer having a molecular weight ranging from 1000 to 6000 and having formula II ##STR5## where n is an integer ranging from 2 to 140; n' and n" are integers the sum of which ranges from 1 to 51.
This polyurethane is particularly useful in extrusion, injection and melt coating operations.
The thermoplastic polyurethane materials of the present invention offer the advantage over the known ones that they have a relatively low hardness (they can attain values of around 86 shore A) and have relatively high melting or softening points, of around 220.degree..
The invention also relates to a process for the preparation of the above mentioned compound, the process comprising reacting a polyetherpolycaprolactone block copolymer of formula IIa ##STR6## with a chain extender of formula HO--R'--OH and with a diisocyanate of formula OCN--R--NCO where R, R', n, n' and n" have the meaning given above. Said chain extender is preferably 1,4-butanediol and said diisocyanate is diphenyl methane 4,4'-diisocyanate, toluene 2,4- and 2,6-diisocyanate, dicyclohexyl methane 4,4'-diisocyanate or 3-isocyanomethyl-3,5,5-trimethylcyclohexyl isocyanate.
The reaction is also preferably conducted by mixing equimolecular amounts of diisocyanate with said chain extender and said polyetherpolycaprolactone block copolymer of formula II, said latter two compounds being in a proportion ranging from 1:1 to 15:1.
It is contemplated that mixing be continuous at a flowrate ranging from 200 to 1500 kg/h of total weight of the ingredients and that it should take place in an extruder at a temperature ranging from 150.degree. to 350.degree. C. and with a mean dwell time ranging from 45 seconds to 2.5 minutes.
The reaction is conducted preferably in the presence of metalcomplex based catalysts proper to the urethane reactions, particularly derivatives of tin and/or bismuth.
The invention also relates to the compound of formula IIa and to a process for the preparation thereof, which is conducted by reacting a polypropylene glycol with terminal hydroxy groups mainly of secondary nature and of formula III ##STR7## where n has the meaning given above, with .epsilon.-caprolactone of formula IV ##STR8##
The thus obtained copolymer comprises terminal hydroxy groups mainly of primary nature in an amount in excess of 60% of the total hydroxy groups.
This reaction comprises the following steps:[a] charging the polypropylene glycol and the .epsilon.-caprolactone in a reactor at room temperature under a flow of nitrogen; [b] heating to a temperature ranging from 100.degree. to 200.degree. C. under a flow of nitrogen for a time ranging from 0.5 to 1.5 hours; [c] adding a metal-complex catalyst up to a temperature ranging from 160.degree. to 250.degree. C.; and [d] maintaining the reaction for a time ranging from 2 to 8 hours.
Some examples of the processes to which the invention relates are given below.
EXAMPLE 1
Preparation of a Formula II Polyol
A reactor at room temperature, with nitrogen flow and mechanical stirring is charged with 2,000 kg of polypropylene glycol and 2,000 kg of .epsilon.-caprolactone.
The raw reaction mass is heated to 120.degree. C. and held at this temperature for an hour so as to remove the water from the starting products.
The raw reaction mass is heated to 200.degree. C. and at this temperature 15 ppm of tin derivative metal-complex catalyst are added. The temperature of the reaction mass is rapidly raised to 220.degree. C. and the evolution of the reaction is checked by gas chromatography. Once the reaction is completed after 5 hours, the reaction mass is cooled to 120.degree. C. and discharged from the reactor at this temperature. The product obtained is stored under a nitrogen atmosphere.
The maximum heat given off at T=200.deg
REFERENCES:
patent: 3051687 (1962-08-01), Young
patent: 4055549 (1977-10-01), Roberts
patent: 4186261 (1980-01-01), Sprey
patent: 4439599 (1984-03-01), Watanabe et al.
patent: 4447591 (1984-05-01), Watanabe et al.
Encyclopedia of Polymer Science, 1988, pp. 275, 276 vol. 13.
Ayuso Piqueras Jose Luis
Julia Barges Joaquim
Gorr Rachel
Merquinsa Mercados Quimicos, S.L.
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