Method of producing polyurethanes

Details Method of producing polyurethanes Method of producing polyurethanes

1982-08-04

1983-09-13

Welsh, Maurice J.

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...

C08G 1880

Patent

active

044043520

DESCRIPTION:

BRIEF SUMMARY
TECHNICAL FIELD

This invention relates to a method of producing polyurethanes, especially for coating purposes.


BACKGROUND OF THE INVENTION

In the conventional processes for producing polyurethanes in the form of coatings using blocked isocyanate compounds, high-temperature baking is required. Therefore, in coating thin steel sheets, there arise such problems as deformation of the steel sheets themselves, melting of solders and excessive energy consumption.
For solution of these problems, there have been proposed such deblocking temperature lowering catalysts for blocked isocyanate compounds as tetrabutyl-1,3-diacetoxydistannoxane, tetrabutyl-1,3-diphenoxydistannoxane, tetrabutyl-1,3-dibenzyloxydistannoxa ne, dibutyltin oxide, dibutyltin dilaurate and tetrabutyltin as disclosed in, for example, Japanese Patent Publication No. 18877/1969 and Japanese Patent Applications laid open (Kokai) under Nos. 42528/1977, 138434/1978 and 138435/1978. However, the effects of these compounds are still unsatisfactory. More efficient catalysts are demanded.


DISCLOSURE OF THE INVENTION

As a result of intensive research by the present inventors, it has now been found that the combined use of at least one mono- or di-organotin compound and a specific amine compound produces still higher catalytic effects as compared with the single use of the organotin compound alone.
Thus, the present invention relates to a method of producing polyurethanes by reacting an at least partially blocked isocyanate compound with an active hydrogen-containing compound in the presence of at least one compound selected from the group consisting of a dialkyltin compound, a diaryltin compound, a monoalkyltin compound and a monoaryltin compound and at least one amine compound selected from the group consisting of 1,10-phenanthroline, bipyridyl, 4,4'-dimethyl-2,2'-bipyridyl, 2,4,6-tris(dimethylaminomethyl)phenol, a morpholine compound, a piperidine compound and an alkanolamine compound of the formula ethyl, propyl, isopropyl, butyl or tert-butyl), phenyl or a group of the formula -(CH.sub.2).sub.m NH.sub.2 wherein m is an integer of 1 to 8, and n is an integer of 1 to 3, and wherein two Rs may be different when n is the integer 1.
The blocked isocyanate compound to be used in practicing the invention includes adducts of polyisocyanate compounds with isocyanate-blocking agents in theoretically calculated weight ratios. Examples of the polyisocyanate compounds, which may be of aromatic, alicyclic or aliphatic series, are tolylene diisocyanate, xylylene diisocyanate, phenylene diisocyanate, bis(isocyanatomethyl)cyclohexane and tetramethylene diisocyanate, and terminal isocyanato group-containing compounds obtained by reacting an excess of any of such polyisocyanates with an active hydrogen-containing low-molecular-weight compound such as ethylene glycol, propylene glycol, trimethylolpropane, hexanetriol and castor oil.
The isocyanate-blocking agents are, for example, phenols (e.g. phenol, m-cresol, xylenol or thiophenol), alcohols (e.g. methanol, ethanol, butanol, 2-ethylhexanol, cyclohexanol, 2-methoxyethanol or 2-ethoxyethanol), and other active hydrogen-containing compounds such as ethyl acetoacetate and diethyl malonate.
Examples of the active hydrogen-containing compound, another basic starting material for producing polyurethanes, are polyether polyols, polyester polyols, polyurethane polyols and epoxy group-containing polyols.
The alkyltin compound, diaryltin compound, monoalkyltin compound and monoaryltin compound to be employed in the practice of the invention include, but are not limited to, dimethyltin oxide, diethyltin oxide, dibutyltin oxide, dioctyltin oxide, diphenyltin oxide, dimethyltin sulfide, dipropyltin sulfide, dibutyltin sulfide, dioctyltin sulfide, dimethyltin diacetate, dimethyltin dibutyrate, dimethyltin dioctanoate, dibutyltin diacetate, dibutyltin dioctanoate, dibutyltin dilaurate, dibutyltin distearate, 1,3-diacetoxy-1,1,3,3-tetrabutyldistannoxane, 1,1,3,3-tetrabutyl-1,3-diphenoxydistannoxane, 1,1,3,3-tetrabutyl-1,3-dilau

REFERENCES:
patent: 3676402 (1972-07-01), Matsui et al.
patent: 3833525 (1974-09-01), Orlando et al.
patent: 4322519 (1982-03-01), Suenobu et al.

Affiliated with

Also associated with

Rating

Method of producing polyurethanes does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of producing polyurethanes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of producing polyurethanes will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1731080