SE424001B - Rigid, Rapid, Solid Polyurethane Product, Which Modifier Contains Chlorinated Aliphatic Compounds, and Procedures for Preparation of Polyurethane Product - Google Patents

Description

7906907-6 preferably within 3 minutes from the time the reactants are mixed together. Upon removal from the mold, the products have sufficient strength to be handled and normally have sufficient strength to be used for their final purpose; however, the physical properties can, if desired, usually be improved by post-curing at elevated temperatures.

The fast-curing, solid, rigid polyurethane products of the present invention are obtained by: mixing and reacting (A) an ammonia- or amine-initiated polyol having an equivalent weight of from 50 to less than 250, preferably from 50 to 200, with (B) a organic polyisocyanate in the presence of (C) a liquid modifier compound having a boiling point above 150 ° C selected from chlorinated aliphatic compounds, wherein components (A) and (B) are present in such amounts that an NCO: OH ratio of from 0 8 to 1.5 are provided, preferably from 0.9 to 1.2 ooh most preferably from 0.95 to 1.05, ooh component (c) is used in an amount of from 5% to 60%, preferably 15-40% by weight , calculated on the total weight of (A), (B) and (C).

Suitable amine-initiated polyols used as component (A) in the present invention include, for example, those prepared by reacting an alkylene oxide with ammonia or an amine having 3-8 active hydrogen atoms.

Suitable amines include, for example, ammonia, ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopropane, 1,6-diaminohexane, diethylenetriamine, triethylenediamine, tetraethylenepentamine, pentethylenhexamine and mixtures thereof.

Suitable alkylene oxides include, for example, ethylene oxide, 1,2-propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, styrene oxide, epichlorohydrin, epibromohydrin, epiodiodhydrin and mixtures thereof.

Suitable organic polyisocyanates used as component (B) of the present invention include, for example, any organic polyisocyanate having two or more NCO groups per molecule and no other substituents capable of reacting with the hydroxy groups of the aminitiated polyoxyalkylene compounds used. as component (C). The isocyanate groups need not be unsubstituted in the aromatic ring. Suitable such polyisocyanates include, for example, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, p, p'-diphenylmethane diisocyanate, p-phenylene diisocyanate, hydrogenated methylenediphenyl diisocyanate, naphthalene diisocyanate, dianisidene ethylene isocyanate, dianisidene ethylene diisocyanate, or more polyisocyanates. Other organic isocyanates which are suitably used and which are to be included in the term organic polyisocyanate include isocyanate-terminated prepolymers prepared from the aforementioned polyols and the above-mentioned isocyanates.

Suitable chlorinated aliphatic compounds having a boiling point above 150 ° C used as a modifying compound in the present invention include, for example, such chlorinated aliphatic compounds as hexachlorobutadiene, tetrachlorobutadiene, 1,2,3,3-tetrachlorobutane, 1,2,3-trichloropropylene. chlorinated paraffins.

The term "liquid modifier boiling above 150 ° C" includes eutectic mixtures of the previously described groups of compounds which form solids at atmospheric pressure but the eutectic mixtures constitute a liquid at room temperature and atmospheric pressure having boiling points above 150 ° C. also includes the solid compounds of the previously described groups which are dissolved in a liquid compound of any of the previously described groups of compounds having boiling points above 150 ° C wherein the resulting solution constitutes a liquid at standard temperature conditions. and pressures having boiling points at atmospheric pressures above 1000 ° C.

Other compounds including inert fillers, for example sand, microballoons, glass fibers, asbestos, aluminum granules and silicon carbide powders, coloring agents such as pigments and dyes including, for example, chromium oxide, ferric oxide and mixtures thereof may be used in the compositions of the present invention.

Suitable materials from which suitable molds for molding the compositions of the present invention can be prepared include polymers, for example, polyethylene, polypropylene, their copolymers and the like, polyurethanes, polysiloxane elastomers, polyethylene terephthalate, cured polyepoxides and mixtures thereof.

It is preferred to use relatively thin-walled molds or molds that have low heat capacity or thermal conductivity.

Heavy molds made of materials with relatively high thermal conductivity, such as aluminum, copper, iron or steel can give rise to hardening problems, ie. the reactants may not be easily removed from the mold unless the mold is preheated to 50-90 ° C, especially when casting relatively thin sections. However, materials with high thermal conductivity, such as copper or aluminum, can be used as thin-walled molds without preheating if the heat capacity of the mold is relatively low compared to the amount of heat released during casting. The compositions of the present invention are suitable as, but not limited to, such uses as a casting material for making bearing surfaces, annular spacers, game pieces, decorative articles, furniture or furniture components, gears or other machine parts, threaded protective plugs and covers.

In some cases, a mixture of components (A) and (B) is so incompatible that the reaction takes place very slowly (ie solidification requires more than 10 minutes). When this occurs, a modifying compound having a high dielectric constant determined at 20 ° C and a frequency of 1x 10 4 cycles per second greater than 4 and preferably greater than 8, for example ethyl acetoacetate, propylene carbonate, acetophenone and dimethyl phthalate may be used. to make the mixture combinable. These compounds help to make components (A) and (B) more compatible in that they can be mixed and will react rapidly to give a fast curing solid which is removable from the mold in less than 5 minutes.

The modifiable miscibility compounds are used in an amount in the range of 2.5-60% of the total weight of components (A), (B) and (C) and such amounts are included as part of the total amount of component (C) which is present in the composition.

In each of the examples and comparative experiments, all the components except the polyisocyanate were thoroughly mixed together and then the polyisocyanate was rapidly mixed into the mixture and immediately poured into a polyethylene mold or a bowl of polyethylene terephthalate.

The compositions, curing times and mold removal times and properties of the products are reported in the following table. 7906907-6 .nmmc fl cvcman fl mmwmwcm fi n uwumømwoom fl w fl om Eow xo flfi ncomm umw: mmm wwuvmš cmu fl a «mßn umnwumnln muonw mH.H om mm om m om 4 mm 4 H .Nm H0MUHH MH | m Hw.0 || mm || nwmn fl om 4 mm 4 4 xwmuwm umä fi ëå fifi šmum flfl w mE0 \ @ cwšuom mc flflfl mum Emnw mæa Emuw%> B Emuw mæa un xwmumm uwmmxwcwm mm fi H> © ßwvwmäwa H5 m flflfl mm Wm m hm øm hm? The amine-initiated polyols used as component (A) in the previous example and comparative experiments were as follows: 72.

The polyisocyanates used as component (B) in the previous examples and comparative experiments were as follows: E1p3§ constituted an 80/20 mixture of the 2,4- / 2,6-isomers of toluene diisocyanate with an NCO equivalent weight of about 87.

The modifiers used as component (C) in the previous example and comparative experiments were as follows: 2Xp_§ was a liquid chlorinated paraffin having a specific gravity of about 1.15, a viscosity at 25 ° C of about 25 poise and containing about 40 weight percent chlorine, commercially available as Chlorowax no. 40 from Diamond Alkali Company. u

Claims (5)

1 7986907-6 PATENT REQUIREMENTS Rigid, fast-cured, solid polyurethane product with a density of at least 1 g / cm 2 plugs or caps, characterized in that it is obtained as a result of mixing the components comprising (A) an ammonia- or amine-initiated polyol having an OH equivalent weight of from 50 to less than 250; (B) an organic polyisocyanate containing an aromatic ring and (C) a liquid modifier compound having a boiling point above 15,000 selected from chlorinated aliphatic compounds having no substituent groups reactive with isocyanate groups wherein components (A) and (B) are present in such amounts that the NCO: OH ratio is from 0.8 to 1.5 and component (C) is used in an amount of 5-60% of the total weight of components (A), (B) and (C). Polyurethane product according to claim 1, characterized in that components (A) and (B) are present in such amounts that the NCO: OH ratio is from about 0.90: 1 to about 1.2: 1 and component (C ) is present in an amount of from about 15% to about 40% by weight of the total weight of components (A), (B) and (C). 3. A polyurethane product according to claim 2, characterized in that components (A) and (B) are present in such amounts that the NCO: OH ratio is from about 0.95: l to about 1.05: 1 Product according to any one of claims 1 to 3, characterized in that component (C) constitutes a chlorinated paraffin. A process for the preparation of solid polyurethane products according to claim 1, characterized in that (A) an ammonia- or amine-initiated polyol having an OH equivalent weight of from 50 to less than 250 is mixed; (B) an organic polyisocyanate containing an aromatic ring and (C) a liquid modifier compound having a boiling point above 150 ° C selected from chlorinated aliphatic compounds having no substituent groups reactive with isocyanate groups, the reaction mixture rapidly to cure and components (A) and (B) are present in such amounts that the NCO: OH ratio is from 0.8 to 1.5 and component (C) is used in an amount of from 5 to 60% of the total weight of components (A), (B) and (C). ANFURDA PUBLICATIONER: us 3 os7 149 (zsóïz fi è)