METHOD FOR MANUFACTURING A POLYURETHANE-MODIFIED FOAM, FOAM OBTAINED, AND USES

Abstract

Disclosed is a method for manufacturing an isocyanurate polyurethane-modified foam, called PUIR, including: a) providing an oil or oil mixture at least 50% by weight of the fatty acids having a carbon chain of C18 or more, the fatty acids having an overall iodine number I.sub.iodine of at least 100 g of I.sub.2/100 g; b) epoxidating at least 50% of the double bonds in the oil to form the corresponding epoxides; and c) directly reacting, in situ, the epoxides that are obtained above with isocyanate or diisocyanate groups for obtaining corresponding oxazolidone derivatives, without passing through the intermediate formation of polyols obtained from epoxides, in the presence of at least one suitable catalyst and at least one expanding agent, so as to obtain the isocyanurate polyurethane-modified foam PUIR. Also disclosed are products, such as rigid insulation material, in particular as a material or panels of rigid insulation for roofing.

Claims

1. Method for manufacturing an isocyanurate polyurethane-modified foam, called PUIR, comprising: a) Providing an oil or a mixture of oils of which at least 50% by weight of the fatty acids have a carbon chain of C18 or more and of which the fatty acids have an overall iodine number I.sub.iodine of at least 100 g of I.sub.2/100 g, b) Epoxidating at least 50% of the double bonds that are present in said oil or said mixture so as to form the corresponding epoxides, c) Directly reacting, in situ, the epoxidized oils that are obtained above with isocyanate or diisocyanate groups for obtaining corresponding oxazolidone derivatives, without passing through the intermediate formation of polyols obtained from epoxides, in the presence of at least one suitable catalyst and at least one expanding agent, so as to obtain said isocyanurate polyurethane-modified foam PUIR.

2. Method according to claim 1, wherein the oil that is used in step a) is an oil that has at least 25% by weight of fatty acids with a carbon chain of at least C20 and whose fatty acids have an overall iodine number I.sub.iodine of at least 200 g of I.sub.2/100 g.

3. Method according to claim 1, wherein the oil that is used in step a) comprises at least one oil that is obtained from at least one microalga.

4. Method according to claim 3, wherein the microalga(e) is/are selected from the group that is formed by: schizochytrium sp., chlorella sp., porphyridium cruentum, pavlova and spirulina.

5. Method according to claim 1, wherein the oil that is used in step a) comprises at least one vegetable oil.

6. Method according to claim 1, wherein step c) is carried out at ambient temperature, or at approximately 20 C.

7. Method according to claim 1, wherein the epoxidation step b) is carried out under hot conditions, at a temperature of between 40 C. and 100 C. for at least 2 hours, using a mixture of hydrogen peroxide and acetic acid.

8. Method according to claim 1, wherein one or more external polyols is/are added in step c).

9. Method according to claim 1, wherein the isocyanate or diisocyanate groups of step c) are provided by aromatic isocyanates or diisocyanates.

10. PUIR foam that can be obtained by implementing the method according to claim 1.

11. PUIR foam that is obtained by implementing the method according to claim 1, wherein the PUIR foam contains at least 10% by mass of an oil that is obtained from microalga(e).

12. PUIR foam that is obtained by implementing the method according to claim 1, wherein the PUIR foam has a level of closed cells that is greater than 90%.

13. A rigid insulation material comprising the PUIR foam according to claim 10.

14. The method of claim 1, wherein the fatty acids have an overall iodine number I.sub.iodine of at least 125 g of I.sub.2/100 g.

15. The method of claim 1, wherein the fatty acids have an overall iodine number I.sub.iodine of at least 150 g of I.sub.2/100 g.

16. The method of claim 5, wherein the vegetable oil comprises canola oil, sunflower oil, linseed oil, and/or soybean oil.

17. The rigid insulation material of claim 13, wherein the rigid insulation material is a rigid thermal insulation material for roofing.

18. The rigid insulation material of claim 17, wherein the rigid insulation material is a rigid thermal insulation panel.

19. Method according to claim 2, wherein the oil that is used in step a) comprises at least one oil that is obtained from at least one microalga.

20. Method according to claim 2, wherein the oil that is used in step a) comprises at least one vegetable oil.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The invention will be explained in connection with the attached drawings, in which:

[0056] FIG. 1 illustrates the structure of a triglyceride, in which R.sub.1, R.sub.2, and R.sub.3 are the various fatty chains;

[0057] FIG. 2 illustrates synthesis of epoxidized triglycerides; and

[0058] FIG. 3 illustrates formation of oxazolidones.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0059] The fact of using an oil of renewable origin with little transformation or few synthetic polyols or none at all makes it possible in particular: [0060] (i) to improve the analysis of the life cycle and the environmental data file on the sealing membranes, [0061] (ii) to be in perfect balance with societal awareness of the environment (Grenelle Forum on the environment), [0062] (iii) to be independent of the provision and cost of fossil resources, [0063] (iv) to use available renewable resources, in particular resources that do not compete with foodstuffs used in other fields, in particular in human and/or animal food (soybean, corn, sunflower . . . ), [0064] (v) to have materials that are thermally stable at higher temperature, this being due to the fact that the oxazolidone bonds are thermally more stable than the urethane or isocyanurate bonds, and [0065] (vi) to have reduced foam prices.

[0066] The reactive compounds (unsaturations on the chains of fatty acids) that are present in the natural oils that are used therefore have the advantage of originating from renewable resources, available in industrial amounts and at competitive prices, with these compounds being, for example, present in a large proportion in the canola oils or the microalgae of the families of schizochytrium or spirulines.

Examples: Manufacturing of a Foam According to the Invention

Epoxidation of Renewable Natural Oils:

[0067] Selection of oils: canola oil Radia 6101 of the Oleon Company with an I.sub.iodine=133 g of I.sub.2/100 g and oil extracted from the schizochytrium sp. microalga with an I.sub.iodine of 266 g of I.sub.2/100 g.

[0068] The oils are totally epoxidized in a conventional way by the method of in-situ formation of paracetic acid according to the following method:

[0069] In a reactor, the oils are mixed with toluene, Amberlite IR-120 H (cation-exchange resin) and acetic acid. The molar ratios between the unsaturations of the oil/Amberlite/acetic acid are as follows: 1/0.5/0.5. The solution is stirred at 70 C., and 1.5 mol of a 30% hydrogen peroxide solution is slowly added to the medium. Once added, the solution is stirred for 7 hours at 70 C. The steps of purification, filtration, and then evaporation of the solvent are then carried out. The canola oils or epoxidized algae oils (respectively HCE and HAE) are thus obtained.

Production of the Foam:

[0070] The isocyanate that is used is a pMDI of the Wanhua Company (Wannate PM-700). The first step is to mix (in % by mass of the total formula)with a propeller mixerthe above-mentioned epoxidized oil, a possible polyol with a silicone surfactant (1%) with DMCHA catalysts and potassium octoate (0.8%), a physical expanding agent such as isopentane (6%) as well as a chemical expanding agent such as water (0.5%). Once the emulsion is produced, isocyanate is added in a possible epoxy-hydroxyl/isocyanate molar ratio=3.

[0071] Foaming is done freely. The reactivity and the characteristics of the foams are compared to a reference foam given with the oxypropylated glycerol polyol (PO) known as ADIANSOL GO 360 of the CECA Company.

Results:

[0072]

TABLE-US-00003 Reference: PO/HCE PO/HAE PO/HAE Polyol Ratio: Ratio: Ratio: (PO) 75/25 75/25 10/90 Biosource Content 4 9 8 29 of Foam Cream Time 20 24 22 34 Filtration Time 129 165 160 225 Stick-Free Time 238 450 375 535 Level of Closed 93 92 93 85 Cells (%) Median Size of 374 441 379 450 Cells (m) Thermal Stability 310 330 335 350 ( C.), ATG Peak under Nitrogen

[0073] Under the industrial conditions of a production line of rigid foam insulation panels, the components are mixed in a high-pressure head (200 bar) at 18 C. The mixture is spread on a 75 m aluminum wall facing and enters a thickness-shaping zone. An aluminum wall facing is unrolled on the surface of the foam so as to have a thermal insulation panel of the type known as Efigreen Acier of the SOPREMA Company.

[0074] Advantageously, the foam that is obtained is used in a rigid thermal insulation panel for applications in the building trade. The latter can be used in turn for insulating floors, walls, or roofs, etc.

[0075] Of course, the invention is not limited to the embodiments described. Modifications are possible, in particular from the standpoint of the composition of the various elements or by substitution of equivalent techniques, without thereby exceeding the scope of protection of the invention.