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...
Reexamination Certificate
1999-05-11
2004-05-04
Sergent, Rabon (Department: 1711)
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...
C528S049000, C528S059000, C528S074500, C528S076000, C528S080000, C528S084000, C528S085000, C560S158000, C560S179000, C560S187000, C560S205000
Reexamination Certificate
active
06730768
ABSTRACT:
FIELD OF THE INVENTION
1. Background of the Invention
This invention relates to the use of special polyols for the production of isocyanate casting resins and coating compositions. The polyols to be used in accordance with the invention may be obtained by reacting epoxidized fatty acid esters of monofunctional C
1-8
alcohols with alcohols having a functionality of 2 to 10. According to the invention, the epoxidized fatty acid esters used are those of which the fatty acid component is based on fatty acid mixtures essentially containing 18 carbon atoms, the oleic acid content of the fatty acid mixtures being at least 80% by weight.
2. Discussion of Related Art
Casting resins are synthetic resins which are either liquid or which can be liquefied by moderate heating and which are cast into open molds and harden therein. Casting resins also include isocyanate casting resins. According to DIN 55958, isocyanate casting resins are synthetic resins which are based on aliphatic, cycloaliphatic or aromatic isocyanates and which still contain free terminal isocyanate groups. They may be cured under various conditions. For example, a one-component casting resin consists of a polyurethane prepolymer terminated by free or blocked isocyanate groups which cure under the effect of moisture, optionally accompanied by heating, for example to accelerate the reaction or to increase strength. A two-component casting resin is based, for example, on polyhydroxy compounds of branched polyesters or polyethers as the first component and on polyisocyanates as the second component. After the two components have been mixed, they cure either at room temperature or at a slightly elevated temperature. Two-component casting resins are used, for example, for encapsulating cable fittings.
According to the teaching of DE-A-43 08 097, isocyanate casting resins or coating compositions which are largely unaffected by moisture and chemicals can be produced by using ring opening and transesterification products of epoxidized fatty acid esters of monofunctional C
1-8
alcohols as polyols. These products can be obtained by reacting the epoxidized fatty acid esters with alcohols having a functionality of preferably 2 to 4. According to Examples 1 to 5 of DE-A-43 08 097, an epoxystearic acid methyl ester of technical quality is used as the starting material. As known to the expert, “technical quality” means that the fatty acid component on which the epoxide stearic acid methyl ester is based is a mixture of—essentially—palmitic acid, stearic acid, oleic acid and linoleic acid, the oleic acid content being about 70% by weight, based on the fatty acid mixture as a whole. One such fatty acid mixture has long been commercially available under the name of Edenor® TiO5 (manufacturer: Henkel KGaA).
Although the polyols according to DE-A-43 08 097 have a number of applicational advantages, they are generally pale yellowish liquids. The yellow color of these products does not present any problems where they are used in casting resins, finishing paints or coatings providing the polyols are reacted with aromatic diisocyanates. However, it does present problems where the polyols are reacted with colorless aliphatic diisocyanates. According to DE-A-44 46 877, the ring opening of epoxides is carried out in the presence of fluoroalkane sulfonic acids as catalyst. In this way, the color quality of the polyols thus produced is improved.
DE-A-40 24 364 describes a process for the production of plastic comonomers and plastics from fats and oils using unsaturated fatty acids, in which crude unsaturated fats and oils are oxidized with performic acid or peracetic acid to form epoxy or hydroxy compounds and, for the production of plastics, are subsequently reacted with difunctional or multifunctional compounds capable of reacting with epoxy and hydroxy groups to form polymers.
DESCRIPTION OF THE INVENTION
The problem addressed by the present invention was to provide polyols which, when used in the production of isocyanate casting resins and coating compositions, would basically show good color quality and, in addition, would show improved color stability during the storage of the corresponding isocyanate casting resins and coating compositions.
It has now surprisingly been found that the problem stated above can be solved by polyols obtainable by reacting epoxidized fatty acid esters of monofunctional C
1-8
alcohols with aliphatic alcohols having a functionality of 2 to 10, the fatty acid component of the epoxidized fatty acid esters being based on fatty acid mixtures essentially containing 18 carbon atoms and the oleic acid content of these fatty acid mixtures being at least 80% by weight, based on the fatty acid mixture as a whole.
The production of the polyols according to the invention is illustrated by reaction scheme 1 below. In this scheme, the substituent R is a C
1-8
alkyl group. Accordingly, the upper formula in scheme 1 represents an oleic acid alkyl ester. It contains a C═C double bond in the 9,10 position of the fatty chain. This double bond is accessible to epoxidation, in which case the associated epoxidized oleic acid alkyl ester is formed, as illustrated in the second formula of scheme 1. This epoxidized oleic acid alkyl ester is then reacted with aliphatic alcohols having a functionality of 2 to 10 to form a corresponding polyol.
Now, if the special fatty alkyl group, i.e. the fatty component of the fatty acid ester, in the first formula of scheme 1 which—in this particular embodiment—stands for an oleic acid alkyl ester, is replaced by a fatty acid mixture essentially containing 18 carbon atoms, the oleic acid content of this fatty acid mixture being at least 80% by weight, based on the fatty acid mixture as a whole, and if this transformation is correspondingly applied to the second formula of scheme 1 remembering that, on this occasion, it is not of course a fatty alkyl group, but rather an epoxyfatty alkyl group which is to be replaced, a general scheme describing the production of the polyols according to the invention would be obtained.
Accordingly, the present invention relates to the use of polyols obtainable by reacting epoxidized fatty acid esters of monohydric C
1-8
alcohols with aliphatic alcohols having a functionality of 2 to 10, the fatty acid component of the epoxidized fatty acid esters being based on fatty acid mixtures essentially containing 18 carbon atoms and the oleic acid content of these fatty acid mixtures, based on the fatty acid mixture as a whole, being at least 80% by weight, for the production of isocyanate casting resins and coating compositions.
According to the invention, the polyols are produced, as mentioned above, by reacting epoxidized fatty acid esters with aliphatic alcohols having a functionality of 2 to 10. This reaction is carried out in accordance with the teaching of DE-A43 08 097 by ring opening and transesterification. Preference is attributed here to the ring opening and transesterification products with alcohols having a functionality of 2 to 7, more particularly to the reaction products with ethylene glycol, propylene glycol, oligomeric ethylene glycols, oligomeric propylene glycols, to the reaction products with glycerol, diglycerol, polyglycerol, trimethylol propane, di-trimethylol propane and/or pentaerythritol. Products such as these can be produced by known methods, the transesterification being carried out during or after the ring opening step by removing the lower alcohol from the reaction equilibrium. Ring opening and transesterification products in which the mole ratio of epoxidized fatty acid ester to the alcohol used for the reaction is 1:1 to 1:10 are preferred. Here, too, 1:1 or 1:2 adducts can be produced analogously to the opening products of epoxidized fatty alcohols.
In one preferred embodiment of the present invention, fatty acid mixtures of sunflower oil from high oleic plants are used as the fatty acid component on which the epoxidized fatty acid esters are based. The fatty acid composition of sunflower oil from high oleic plants is as follows: 80 t
Gruetzmacher Roland
Heidbreder Andreas
Nagorny Ulrich
Westfechtel Alfred
LandOfFree
Methods of preparing casting resins and coating compositions... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Methods of preparing casting resins and coating compositions..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods of preparing casting resins and coating compositions... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3224799