Use of 1,1,1,4,4,4-hexafluorobutane as a blowing and insulating agent for the production of synthetic foams.

The present invention relates to the use of Dämmgases and blowing agent 1,1,1,4,4,4-hexafluorobutane (R 356) for the production of plastic foams, in particular foams based on isocyanate, preferably polyurethane foams.

It is known that foams prepared using blowing agents. In closed-cell foams are these also be effective as a heat insulating gas cell. Among the most commonly used today insulation and propellants for polyurethane foams, polystyrene, polyvinyl chloride, phenol-formaldehyde, inter alia, include the chlorofluorocarbon trichlorofluoromethane (R11), dichlorodifluoromethane (R 12), trichlorotrifluoroethane (R 113), among others.

These products, however, have the drawback that they reach due to their high stability in the stratosphere, where they are to contribute to the reduction of the ozone present there due to their chlorine content. For this reason, the world production was limited to chlorofluorocarbons substances.

The invention is based on finding Dämmgase and blowing agents for the production of plastic foams that can not damage the ozone layer on the object.

This object is achieved with the inventive insulation and propellant 1,1,1,4,4,4-Hexafluorobutane.

The invention relates to the use of 1,1,1,4,4,4-hexafluorobutane as blowing and Dämmgas in the production of plastic foams. According to a preferred embodiment of the invention is 1,1,1,4,4,4-hexafluorobutane in an amount of 2-30 wt .-%, preferably in an amount of 2-15 wt .-%, in particular in an amount of 2 -8 wt .-%, based on the plastic foam used.

Preferably according to the invention is the production of isocyanate-based foams, in particular the production of polyurethane foams and / or the production of polyisocyanurate foams.

The preparation of plastic foams using propellant gases is well known.

The production of foams based on isocyanate is known per se and, for example in German Offenlegungsschriften 1,694,142, 1,694,215 and 1,720,768 and in Volume VII, Polyurethane, edited by Vieweg and Hoechtlen, Carl Hanser Verlag Munich 1966 Plastics Handbook and in the new edition of this book, edited by G. Oertel, Carl Hanser Verlag, Munich, Vienna, 1983.

This is mainly to urethane and / or isocyanurate and / or allophanate and / or uretdione and / or urea and / or carbodiimide groups. The use according to the invention is preferably carried out in the production of polyurethane and polyisocyanurate foams.

For the production of isocyanate-based foams are used:<ul><li>1. As starting components, aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic polyisocyanates, such as are described for example by W. Siefken in Liebigs Annalen, 562, pages 75 to 136, for example those of the formula Q (NCO)_n in the n = 2-4, preferably 2-3, and Q represents an aliphatic hydrocarbon radical having 2-18, preferably 6-10 carbon atoms, a cycloaliphatic hydrocarbon radical with 4-15, preferably 5-10 carbon atoms, an aromatic hydrocarbon radical with 6-15, preferably 6-13 carbon atoms or a araliphatic hydrocarbon radical with 8-15, preferably 8-13 carbon atoms, for example those polyisocyanates as they are described in DE-OS 28 32 253, pages 10-11,. Particular preference is usually the commercially available polyisocyanates, for example 2,4- and 2,6-diisocyanate, and mixtures of these isomers ( "TDI"); Polyphenyl, such as are produced by aniline-formaldehyde condensation and subsequent phosgenation ( "crude MDI") and polyisocyanates containing carbodiimide, urethane, allophanate, isocyanurate, urea or biuret groups ( "modified polyisocyanates"), especially those modified polyisocyanates which are by themselves 2,4- and / or 2,6-toluylene diisocyanate or from 4,4'- and / or 2,4'-diphenylmethane diisocyanate.</li><li>2. starting components are compounds having at least two isocyanate-reactive hydrogen atoms and having a molecular weight usually of 400 to 10,000. These are understood compounds containing amino groups, thiol groups or carboxyl groups, preferably compounds containing hydroxyl groups, in particular 2 to 8 compounds containing hydroxyl groups, especially those having a molecular weight of 1,000 to 6,000, preferably 2,000 to 6,000, for example at least 2, generally 2 to 8, but preferably 2 to 6, hydroxyl groups and polyether polyesters, polycarbonates and polyesteramides, as are known for the production of homogeneous and cellular polyurethanes and as are described for example in DE-OS 28 32 253, pages 11-18,.</li><li>3. You may need more starting components compounds having at least two isocyanate-reactive hydrogen atoms and a molecular weight of 32 to 399. In this case, one understands having hydroxyl groups and / or amino and / or thiol groups and / or carboxyl groups, preferably hydroxyl groups and / or amino groups which serve as chain extenders or crosslinking agents. These compounds generally have 2 to 8, preferably 2 to 4, isocyanate reaction hydrogen atoms on. Examples are described in DE-OS 28 32 253, pages 19-20,.</li><li>4. 1,1,1,4,4,4-Hexafluorobutane as fuels and Dämmgas.</li><li>5. Where appropriate, auxiliaries and additives are also used as<ul><li>a) water and / or other readily volatile organic substances as propellants,</li><li>b) additional catalysts of the type known per se in amounts up to 10 wt .-%, based on the amounts of component 2,</li><li>c) surface-active additives such as emulsifiers and foam stabilizers;</li><li>d) reaction retarders, for example acidic substances such as hydrochloric acid or organic acid halides, cell regulators known per se such as paraffins or fatty alcohols or dimethylpolysiloxanes and pigments or dyes and other flame retardants of the type known per se, for example tricresyl phosphate, also stabilizers against aging and weathering , Plasticizers and fungistatic and bacteriostatic substances and fillers such as barium sulfate, kieselguhr, carbon black or whiting.</li></ul></li></ul>

These optional auxiliaries and additives are described for example in DE-OS 27 32 292, pages 21-24,.

Further examples of optionally present invention surface-active additives and foam stabilizers, cell regulators, reaction, stabilizers, flame retardants, plasticizers, dyes and fillers and fungistatic and bacteriostatic substances and details concerning the use and action of these additives are described in Kunststoff-Handbuch, Volume VII, edited described by Vieweg and Hochtlen, Carl Hanser Verlag, Munich 1966, on pages 103-113.

The isocyanate-based foams are prepared in a conventional manner.

Carrying out the method for the production of polyurethane plastics: The reaction components are brought to the one-shot, prepolymer or semi-prepolymer which is known per se to implement, often using mechanical devices to eg those which are described in US Patent No. 27 64 565th Details of processing equipment which is also according to the invention are suitable, are Volume VII, edited by Vieweg and Hoechtlen, Carl Hanser Verlag, Munich 1966, eg on pages 121 to 205, in Kunststoff-Handbuch,.

According to the invention can also be cold-hardening foams (cf.. GB-PS 11 62 517, DE-OS 21 53 086).

but of course also possible to produce foams by block foaming or by the laminator process known per se.

The products obtainable according to the invention for example, as insulation panels for roof insulation applications.

I. Preparation of 1,1,1,4,4,4-hexafluorobutane

example A

In a stainless steel autoclave, 40 g of 1,1,1,4,4,4-hexafluoro-2-chloro-buten-2 ¹⁾ in 300 ml of ethanol in the presence of 12 g of potassium hydroxide and 25 g of Raney nickel for 3 hours at 20 ° C and 1 hour at 100 ° C with hydrogen. The pressure was placed bar in range from 30 to 40th Thereafter, from the reaction mixture, the solid components were separated by filtration and the remaining liquid is worked up by distillation. There, 16 g of 1,1,1,4,4,4-hexafluorobutane were obtained with a boiling point of 25 to 30 ° C at 1013 mbar. The mass spectrum showed a value for 166 M⁺ / e.

1) see "Preparation, Properties and Technology of Fluorine and Organic Fluoro Compounds", editor CH. Slessner and SR Schram, McGraw-Hill Book Company, Inc., New York, Toronto, London 1951, page 817)

example B

199 g (1 mol) of 1,1,1,4,4,4-hexafluoro-2-chloro-2-butene were dissolved in 800 ml of diglyme and in the presence of 45 g of sodium hydroxide and 30 g of Raney nickel in the temperature range of 20 to 40 ° C and hydrogenated at a hydrogen pressure of 20 to 40 bar. After filtering off the solid constituents, the solvent was extracted with water and the separated organic phase is purified by fractional distillation. The yield of 1,1,1,4,4,4-Hexafluorobutane was 125 g (75% of theory), the boiling point of 24 to 27 ° C at 1013 mbar. The ¹⁹F NMR spectrum showed a peak at -10.7 ppm (Standard: CF₃CO₂H).

example C

10 g (36 mmol) of 1,1,1,4,4,4-hexafluoro-2-bromo-3-chloro-2-butene (see U.S. Patent 3,567,788) were dissolved in 50 ml of tetrahydrofuran in the presence of 3.0 g of sodium hydroxide and 5 g of Raney nickel bar hydrogenated in the temperature range of 20 to 40 ° C and at a hydrogen pressure of 20 to 40th It was worked up as described in Example B. The yield was 3.5 g of 1,1,1,4,4,4-Hexafluorobutane (= 59% of theory).

example D

40 g (0.2 mol) of 1,1,1,4,4,4-hexafluoro-2-chloro-buten-2 were mixed with 12 g of potassium hydroxide in 300 ml ethanol in a pressure range of 20 to 40 bar and at a temperature of 20 to 100 ° C is hydrogenated in the presence of 25 g Raney nickel. After filtering off the solid constituents, the solvent was extracted with water and the separated organic phase purified by distillation. It 15.5 g (= 47% of theory) of 1,1,1,4,4,4-Hexafluorobutane obtained. The boiling point was 24 to 27 ° C at 1013 bar.

example e

23.5 g (0.1 mol) of 1,1,1,4,4,4-hexafluoro-2,3-dichloro-2-butene (see U.S. Patent 3,567,788) were mixed with 50 ml of tetrahydrofuran, 8.5 g of sodium hydroxide and 3 g of a catalyst are added, the 5 wt .-% of palladium on carbon. This mixture was stirred at temperatures between 20 and 40 ° C with water fuel at pressures ranging from 20 to 40 hydrogenated bar. The workup of the reaction mixture was carried out as described in Example B. The yield was 8.0 g (= 75% of theory) of 1,1,1,4,4,4-Hexafluorobutane.

II. Preparation of polyurethane foams

example 1

<tables id="tabl0001" num="0001"><table frame="all"><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><tbody valign="top"><row><entry namest="col1" nameend="col1" align="char" char=",">100</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">a polyether with hydroxyl value of 380, which was obtained by addition of propylene oxide to a solution of saccharose, propylene glycol and water,</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">2</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">a Siloxanpolyethercopolymers as a foam stabilizer,</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">3.8</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">water and</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">3</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">Dimethylcyclohexylamine as a catalyst were mixed.</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">100</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">this mixture with</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">15</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">1,1,1,4,4,4-Hexafluorobutane intensively mixed as a blowing agent using a laboratory stirrer.</entry></row></tbody></tgroup></table></tables>

This mixture was foamed with 152 g of crude 4,4'-diisocyanatodiphenylmethane. It was a hard polyurethane foam: foaming and physical data:<tables id="tabl0002" num="0002"><table frame="all"><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">time spent</entry><entry namest="col2" nameend="col2" align="left">(S)</entry><entry namest="col3" nameend="col3" align="right">: 10</entry></row><row><entry namest="col1" nameend="col1" align="left">setting time</entry><entry namest="col2" nameend="col2" align="left">(S)</entry><entry namest="col3" nameend="col3" align="right">: 44</entry></row><row><entry namest="col1" nameend="col1" align="left">free bulk density</entry><entry namest="col2" nameend="col2" align="left">(Kg / m³)</entry><entry namest="col3" nameend="col3" align="right">: 25</entry></row><row><entry namest="col1" nameend="col1" align="left">cell image</entry><entry namest="col2" nameend="col2" /><entry namest="col3" nameend="col3" align="right">: fine</entry></row></tbody></tgroup></table></tables>

example 2

<tables id="tabl0003" num="0003"><table frame="all"><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><tbody valign="top"><row><entry namest="col1" nameend="col1" align="char" char=",">60</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">a polyether having an hydroxyl number 950, which has been obtained by addition of propylene oxide to trimethylolpropane,</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">40</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">a polyether having an hydroxyl number of 56, which has been obtained by adding propylene oxide to trimethylolpropane,</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">0.5</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">water and</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">2</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">a Siloxanpolyethercopolymers as a foam stabilizer were mixed.</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">100</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">this mixture with</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">10</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">1,1,1,4,4,4-Hexafluorobutane intensively mixed as a blowing agent using a laboratory stirrer.</entry></row></tbody></tgroup></table></tables>

This mixture was foamed with 164 g of crude 4,4'-diisocyanatodiphenylmethane. The result is a rigid polyurethane foam of high density. Foaming and physical data:<tables id="tabl0004" num="0004"><table frame="all"><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">time spent</entry><entry namest="col2" nameend="col2" align="left">(S)</entry><entry namest="col3" nameend="col3" align="right">: 80</entry></row><row><entry namest="col1" nameend="col1" align="left">setting time</entry><entry namest="col2" nameend="col2" align="left">(S)</entry><entry namest="col3" nameend="col3" align="right">: 130</entry></row><row><entry namest="col1" nameend="col1" align="left">free bulk density</entry><entry namest="col2" nameend="col2" align="left">(Kg / m³)</entry><entry namest="col3" nameend="col3" align="right">: 73</entry></row><row><entry namest="col1" nameend="col1" align="left">compacted overall foam</entry><entry namest="col2" nameend="col2" align="left">(Kg / m³)</entry><entry namest="col3" nameend="col3" align="right">: 350</entry></row><row><entry namest="col1" nameend="col1" align="left">cell image</entry><entry namest="col2" nameend="col2" /><entry namest="col3" nameend="col3" align="right">: fine</entry></row></tbody></tgroup></table></tables>

example 3

<tables id="tabl0005" num="0005"><table frame="all"><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><tbody valign="top"><row><entry namest="col1" nameend="col1" align="char" char=",">91</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">a polyether having an hydroxyl number of 56, which has been obtained by adding propylene oxide to trimethylolpropane,</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">9</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">Monoethylene glycol and</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">0.1</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">Of water were mixed.</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">100</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">this mixture with</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">15</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">1,1,1,4,4,4-Hexafluorobutane intensively mixed as a blowing agent using a laboratory stirrer.</entry></row></tbody></tgroup></table></tables>

This mixture was foamed with 56 g of crude 4,4'-diisocyanatodiphenylmethane. There was a viscoelastic polyurethane foam. Foaming and physical data:<tables id="tabl0006" num="0006"><table frame="all"><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">time spent</entry><entry namest="col2" nameend="col2" align="left">(S)</entry><entry namest="col3" nameend="col3" align="right">: 35</entry></row><row><entry namest="col1" nameend="col1" align="left">setting time</entry><entry namest="col2" nameend="col2" align="left">(S)</entry><entry namest="col3" nameend="col3" align="right">: 105</entry></row><row><entry namest="col1" nameend="col1" align="left">free bulk density</entry><entry namest="col2" nameend="col2" align="left">(Kg / m³)</entry><entry namest="col3" nameend="col3" align="right">: 127</entry></row><row><entry namest="col1" nameend="col1" align="left">cell image</entry><entry namest="col2" nameend="col2" /><entry namest="col3" nameend="col3" align="right">: fine</entry></row></tbody></tgroup></table></tables>

example 4

<tables id="tabl0007" num="0007"><table frame="all"><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><tbody valign="top"><row><entry namest="col1" nameend="col1" align="char" char=",">100</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">a polyether having an hydroxyl number of 56, which has been obtained by adding propylene oxide to trimethylolpropane,</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">3</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">Water,</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">1</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">a Siloxanpolyethercopolymers as a foam stabilizer,</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">0.05</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">Of dibutyltin dilaurate were mixed.</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">100</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">this mixture with</entry></row><row><entry namest="col1" nameend="col1" align="char" char=",">10</entry><entry namest="col2" nameend="col2" align="left">G</entry><entry namest="col3" nameend="col3" align="left">1,1,1,4,4,4-Hexafluorobutane intensively mixed as a blowing agent using a laboratory stirrer.</entry></row></tbody></tgroup></table></tables>

This mixture was foamed with 41 g toluene diisocyanate. There was a soft polyurethane foam. Foaming and physical data:<tables id="tabl0008" num="0008"><table frame="all"><tgroup cols="3" colsep="1" rowsep="0"><colspec colnum="1" colname="col1" colwidth="52.50mm" /><colspec colnum="2" colname="col2" colwidth="52.50mm" /><colspec colnum="3" colname="col3" colwidth="52.50mm" /><tbody valign="top"><row><entry namest="col1" nameend="col1" align="left">time spent</entry><entry namest="col2" nameend="col2" align="left">(S)</entry><entry namest="col3" nameend="col3" align="right">: 7</entry></row><row><entry namest="col1" nameend="col1" align="left">setting time</entry><entry namest="col2" nameend="col2" align="left">(S)</entry><entry namest="col3" nameend="col3" align="right">100</entry></row><row><entry namest="col1" nameend="col1" align="left">free bulk density</entry><entry namest="col2" nameend="col2" align="left">(Kg / m³)</entry><entry namest="col3" nameend="col3" align="right">: 27</entry></row><row><entry namest="col1" nameend="col1" align="left">cell image</entry><entry namest="col2" nameend="col2" /><entry namest="col3" nameend="col3" align="right">: fine</entry></row></tbody></tgroup></table></tables>