WO2018202417A1

WO2018202417A1 - A cooler

Info

Publication number: WO2018202417A1
Application number: PCT/EP2018/059778
Authority: WO
Inventors: Orcun YUCEL; Sefa Yasin UZEN
Original assignee: Arcelik Anonim Sirketi
Priority date: 2017-05-05
Filing date: 2018-04-17
Publication date: 2018-11-08
Also published as: TR201706646A2

Abstract

The present invention relates to polyurethane foam used as insulating material in coolers.

Description

A COOLER

The present invention relates to nanoclay compounded rigid polyurethane foam formulation developed to be used for insulation purposes in coolers.

The plastic foams, also called foamed plastic or cellular plastic, are chemical structures formed by dispersion of gaseous phase in solid phase (polymeric matrix). Both thermoplastics and thermoset plastics can be obtained in a cellular structure by changing their production conditions. The characteristics of plastic foam are determined by the chemical nature, the composition of solid polymeric phase, and the structure and the dimension of its cells. The plastic foams have various areas of utilization since they have various structures and characteristics, and are light-weight and low-cost. Foam materials find more significant application areas every passing day thanks to advances in foam technology and development of new foam structures.

Polyurethane foam is composed of two principal raw materials, and catalyst/catalysts and surfactant/surfactants (9) enabling said raw materials to react chemically, and an agent/agents enabling them to expand. These two principal raw materials are base polyol (containing hydroxyl group) and isocyanate. Polyol systems are composition of a catalyst, a surfactant, a blowing agent and other chemicals introduced into polyether- or polyester- based polyols in appropriate proportions. This compositions include free hydroxyl (OH). Isocyanates, on the other hand, are chemicals carrying free NCO, and reacting in an exothermic reaction when mixed with a polyol system. The isocyanates are described and named according to the percentage/ number of the NCO that they carry. Polyurethanes form as a result of repetitively continuing polymerization of isocyanates containing NCO group, and polyols having OH group in their structures. Polymerization is an exothermic reaction, and polyurethanes of varying structures can be obtained by using polyols and isocyanates of varying molecular structures.

Since expansion in polyurethane polymerization reaction is three dimensional, the polyurethane fills into all cavities of the container or mold in which it is disposed and assumes its shape. Spreading characteristics of polyurethane foams are highly superior to other chemical products. The OH and NCO percentages of the components determine the foam being rigid, semi-rigid or flexible. The application areas of polyurethane foam vary according to the chemical structure of the foam.

The elapsed time from mixing polyol and isocyanate in desired proportions to each other, to forming of the polyurethane foam is divided into three stages. These three stages determining the chemical reaction characteristics of polyurethane foam are; creaming time, gelation time. The thermal conductivity coefficient of conventional polyurethane foams are generally at the level of 21 mW/mK, and their compression strength is at the level of 120-130 kPa.

State of the art U.S. patent application no. US 6518324 B1 discloses polymer foams with high thermal insulation values, containing nanoclay.

State of the art U.S. patent application no. US 6802997 B2 discloses a method for producing rigid polyurethane foam material, a method for producing a refrigerator using said foam material, and a refrigerator produced by the same method.

State of the art U.S. patent application no. US 5120771 A discloses a polyurethane foam production method using polyol, isocyanate, water, acetone and catalyst.

The aim of the present invention is to produce a cooler comprising as insulation material a rigid polyurethane foam with low thermal conductivity coefficient and high compression strength.

The rigid polyurethane foam formulation realized to achieve the aim of the present invention and disclosed in the first claim and the dependent claims, is produced by the process comprising the processing steps of:
(i) Modification of nanoclay with alkali added acid,
(ii) Mixing the modified nanoclay and isocyanate by a mixer,
(iii) Pumping said mixture to a high-power probe ultrasonication device, and performing ultrasonication while the mixture is flowing in said device to obtain a good dispersion,
(iv) Cooling the heated and mixed material in the cooling unit (6),
(v) Pumping the cooled nanoclay compounded isocyanate mixture (component A) into a storage tank at the injection machine and keeping it there for a period of time,
(vi) Meanwhile, pumping polyol (8), surfactant/surfactants (9), catalyst/catalysts (10) and pure water (11) (component B) in a separate storage tank at the injection machine, and keeping the mixture there for a period of time while mixing,
(vii) Mixing a blowing gas material with component B in the storage tank while the materials are kept in the storage tank,
(viii) Then, simultaneously pumping the components A and B to an injection head (13),
(ix) Mixing the components A and B in the injection head (13) and occurrence of polyurethane foam reaction, and
(x) Molding the polyurethane released from the injection head (13) by injecting it to the molds (14).

The rigid polyurethane foam formulation of the invention comprises a base polyol (containing hydroxyl group) (8), nanoclay compounded isocyanate, surfactant (9), catalyst (10), pure water (11) and blowing gas.

The rigid polyurethane foam of the invention is utilized as cooler insulation material.

The process related to the production of the rigid polyurethane foam realized to achieve the aims of the present invention, and the result of the thermal conduction analysis related to said polyurethane foam are illustrated in the accompanying drawing, wherein:

Figure 1 is a schematic view of the process related to the production of the rigid polyurethane foam of the invention.

The elements in the figures are numbered individually and the correspondence of these numbers are given hereinafter.

Nanoclay
Organic modification
Organoclay
Mixer and ultrasonication probe
MDI (methyl diisocyanate)
Cooling unit
Back feeding unit
Polyol
Surfactant
Catalyst
Pure water
Storage unit and injection machine
Injection head
Mold

Rigid polyurethane foam is produced by the process comprising the processing steps of:
(i) Mixing nanoclay additive (1) and isocyanate (component A),
(ii) Mixing polyol (8), surfactant/surfactants (9), catalyst/catalysts (10) and pure water (11) (component B),
(iii) Then mixing the components A and B and occurrence of polyurethane foam reaction, and
(iv) Molding the obtained polyurethane by injecting it to the molds (14).

The rigid polyurethane foam of the invention is produced by the process comprising the processing steps of:
a) modification of nanoclay additive (1) with alkali added acid, before the processing step of mixing nanoclay additive (1) and isocyanate (component A),
b) Pumping the modified nanoclay and isocyanate mixture to a high-power probe ultrasonication device, and performing ultrasonication while the mixture is flowing therein to obtain a good dispersion,
c) Cooling the heated and mixed component A in a cooling unit (6),
d) Pumping the cooled nanoclay compounded isocyanate mixture (component A) into a storage tank at the injection machine and keeping it there for a period of time while mixing,
e) After the processing step of mixing polyol (8), surfactant/surfactants (9), catalyst/catalysts (10) and pure water (11) (component B), pumping component B into a separate storage tank in the injection machine, and keeping the mixture there for a period of time while mixing,
f) Mixing a blowing gas material with component B in the storage tank while the materials are kept in the storage tank, and
g) simultaneously pumping the components A and B to the injection head (13), before the processing step of mixing the components A and B and occurrence of polyurethane foam reaction,

Mixing the nanoclay additive (1) with isocyanate enhances strength and reduces the thermal conductivity coefficient. Modifying the nanoclay additive (1) with alkali added acid, enables dissolution of clay in polymer. In addition, the mixing performed by the probe ultrasonication device in processing step (b) enables the component A (nanoclay additive (1) + isocyanate) to be mixed much more homogeneously. Cooling is performed for cooling the component A which is heated while mixing in processing step (b),

The processing steps (i) and (b) of the rigid polyurethane foam production of the invention are performed in a temperature range of 40-60°C, with a power in the range of 180-400 W and for a period of 10-15 minutes.

Performing of the processing steps (i) and (b) in the above-stated ambient conditions enables obtaining a more homogeneous mixture.

The processing step (c) of the rigid polyurethane foam production of the invention is performed in room conditions.

Performing of the processing step (c) in room conditions reduces the costs and enables obtaining a more efficient mixture.

The processing steps (d), (e) and (f) of the rigid polyurethane foam production of the invention are performed in a temperature range of 23-28°C, under 6-10 bar pressure, and for a period of 30-60 minutes.

Performing of the processing steps (d), (e) and (f) in the above-stated ambient conditions enables obtaining a more homogeneous mixture and creating suitable conditions for reaction.

An embodiment of the invention optionally comprises after the processing step (c), the processing step of feeding the component A to the probe ultrasonication device by a back feeding unit (7).

The mixture fed to the probe ultrasonication device by the back feeding unit (7), transforms into a more homogeneous mixture thanks to this repeated processing.

Polyether based polyol (8) is used in the rigid polyurethane foam production of the invention.

Polyether based polyol (8) reduces production costs.

In the preferred embodiment of the invention, polyether based formulated polyol is used in rigid polyurethane foam production.

In the preferred embodiment of the invention, nanoclay additive (1) modified with sodium (Na) added acid is used in rigid polyurethane foam production.

Modification of nanoclay additive (1) with sodium added acid is opted due to sodium being a low-cost, readily available and high-performance alkali.

In the rigid polyurethane foam production of the invention, as the nanoclay additive (1), inorganic clay materials are used such as: montmorillonite, vermiculite, kaolinite, talk, halloysite or sepiolite.

In the preferred embodiment of the invention, halloysite is used as the nanoclay additive (1) in rigid polyurethane foam production.

Using halloysite as the nanoclay additive (1) enhances the thermal insulation performance and the compression strength of the rigid polyurethane foam. Nano-sized halloysite having a three-dimensional needle-like shape gives it a large surface area. And a larger surface area enhances its nucleating agent effect in the rigid polyurethane, reducing the wall size and the thermal conduction coefficient of the rigid polyurethane. Halloysite also has a compression strength increasing effect as it is silica based.

In the preferred embodiment of the invention, the nanoclay additive (1) is used in a ratio of 0.5-1.5% in rigid polyurethane foam production.

In the preferred embodiment of the invention, methyl diisocyanate (MDI) (5) is used as isocyanate in rigid polyurethane foam production.

In the preferred embodiment of the invention, the ratio of MDI (5): nanoclay additive (1) is in the range of 100:1 and 100:3.

In the rigid polyurethane foam production of the invention, high-purity cyclopentane or isobuthane/cyclopentane mixture is used as the blowing gas.

Since they are silica based, using cyclopentane or isobuthane/cyclopentane mixture reduces the wall size, increases the proportion of enclosed cells and thus enhances the compression strength. This also reduces the density which in turn reduces viscosity, providing ease of flow in the pump line.

In the preferred embodiment of the invention, amine based catalyst/catalysts (10) are used in rigid polyurethane foam production.

In the rigid polyurethane foam production of the invention, Bis(2-dimethylaminoethyl)(methyl)amine (C9H23N3 based), Cyclohexyldimethylamine (C8H17N based) and N,N,N',N',N'',N''-Hexamethyl-1,3,5-triazine-1,3,5(2H,4H,6H)-tripropanamine (C18H42N6) combinations are used as catalyst (10).

In the preferred embodiment of the invention, in rigid foam polyurethane production, the proportions of Bis(2-dimethylaminoethyl)(methyl)amine (C9H23N3 based), Cyclohexyldimethylamine (C8H17N based) and N,N,N',N',N'',N''-Hexamethyl-1,3,5-triazine-1,3,5(2H,4H,6H)-tripropanamine (C18H42N6) catalysts (10) to each other are in the range of 1.50:1:0.5 – 1.75:1:0.8.

The rigid polyurethane foam obtained by the polyurethane production method of the invention, comprises formulated polyol, isocyanate compounded with nanoclay modified with alkali added acid, and blowing gas.

The rigid polyurethane foam obtained by the polyurethane production method of the invention, comprises formulated polyol in the ratio of 35-45 % by weight, isocyanate compounded with nanoclay modified with alkali added acid in the ratio of 30-60 % by weight, and blowing gas in the ratio of 4-6 % by weight.

In the preferred embodiment of the invention, the formulated polyol present in the rigid polyurethane foam content comprises polyol (8), surfactant (9), catalyst (10) and pure water (11).

In the preferred embodiment of the invention, the formulated polyol present in the rigid polyurethane foam content comprises polyol (8) in the ratio of 90-99 % by weight, surfactant (9) in the ratio of 0.3-0.5 % by weight, catalyst (10) in the ratio of 0.1-0.2 % by weight and pure water (11) in the ratio of 0.3-0.5 % by weight.

The polyol (8) used in the rigid polyurethane foam of the invention is polyether based polyol (8).

In the preferred embodiment of the invention, the rigid polyurethane foam comprises isocyanate compounded with nanoclay modified with sodium (Na) added acid.

The rigid polyurethane foam of the invention comprises as the nanoclay additive (1) inorganic clay materials such as: montmorillonite, vermiculite, kaolinite, talk, halloysite or sepiolite.

In the preferred embodiment of the invention, the rigid polyurethane foam comprises halloysite as the nanoclay additive (1).

In the preferred embodiment of the invention, the rigid polyurethane foam comprises nanoclay additive (1) in the ratio of 0.5-1.5 % by weight.

In the preferred embodiment of the invention, the rigid polyurethane foam comprises methyl diisocyanate (MDI) (5) as isocyanate.

The rigid polyurethane foam of the invention comprises high-purity cyclopentane or isobuthane/cyclopentane mixture as the blowing gas.

The rigid polyurethane foam of the invention comprises amine based catalyst/catalysts (10).

In the preferred embodiment of the invention, the rigid polyurethane foam comprises as catalyst (10) combinations of: Bis(2-dimethylaminoethyl)(methyl)amine (C9H23N3 based), Cyclohexyldimethylamine (C8H17N based) and N,N,N',N',N'',N''-Hexamethyl-1,3,5-triazine-1,3,5(2H,4H,6H)-tripropanamine (C18H42N6).

In an embodiment of the invention, the rigid polyurethane foam comprises combinations of : Bis(2-dimethylaminoethyl)(methyl)amine (C9H23N3 based), Cyclohexyldimethylamine (C8H17N based) and N,N,N',N',N'',N''-Hexamethyl-1,3,5-triazine-1,3,5(2H,4H,6H)-tripropanamine (C18H42N6) whose proportions to each other are in the range of 1.50:1:0.5 – 1.75:1:0.8.

The cooler comprises as insulation material: rigid polyurethane foam produced by the rigid polyurethane foam production method of the invention.

Claims

Rigid polyurethane production method, comprising the processing steps of:

(i) mixing nanoclay additive (1) and isocyanate (component A),

(ii) mixing polyol (8), at least one surfactant (9), at least one catalyst (10) and pure water (11) (component B),

(iii) then mixing the components A and B and occurrence of polyurethane foam reaction, and

(iv) molding the obtained polyurethane by injecting it to the molds (14),

characterized by the processing steps of:

(a) modification of nanoclay additive (1) with alkali added acid, before the processing step of mixing nanoclay additive (1) and isocyanate (component A),

(b) pumping the modified nanoclay and isocyanate mixture to a high-power probe ultrasonication device, and performing ultrasonication while the mixture is flowing therein to obtain a good dispersion,

(c) cooling the heated and mixed component A in a cooling unit (6),

(d) pumping the cooled nanoclay compounded isocyanate mixture (component A) into a storage tank at the injection machine and keeping it there for a period of time while mixing,

(e) after the processing step of mixing polyol (8), surfactant/surfactants (9), catalyst/catalysts (10) and pure water (11) (component B), pumping component B into a separate storage tank at the injection machine, and keeping the mixture there while mixing,

(f) mixing a blowing gas material with the component B in the storage tank while the materials are kept in the storage tank, and

(g) simultaneously pumping the components A and B to the injection head (13), before the processing step of mixing the components A and B and occurrence of polyurethane foam reaction.
Rigid polyurethane production method according to claim 1, characterized in that the processing steps (i) and (b) are performed in a temperature range of 40-60°C, with power in the range of 190-400 W, and for a period of 10-15 minutes.
Rigid polyurethane production method according to claim 1, characterized in that the processing step (c) is performed in room conditions.
Rigid polyurethane production method according to claim 1, characterized in that the processing steps (d), (e) and (f) are performed in a temperature range of 23-28°C, under 6-10 bar pressure and for a period of 30-60 minutes.
Rigid polyurethane production method according to claim 1, characterized by the processing step of feeding the component A to the probe ultrasonication device by the back feeding unit (7), optionally after the processing step (c),.
Rigid polyurethane production method according to claim 1, characterized by using polyether based polyol (8).
Rigid polyurethane production method according to claim 6, characterized by using polyether based formulated polyol (8).
Rigid polyurethane production method according to claim 1, characterized by using nanoclay additive (1) modified with sodium (Na) added acid.
Rigid polyurethane production method according to claim 1, characterized by using as the nanoclay additive (1) inorganic clay materials such as montmorillonite, vermiculite, kaolinite, talk, halloysite or sepiolite.
Rigid polyurethane production method according to claim 9, characterized by using halloysite as the nanoclay additive (1).
Rigid polyurethane production method according to claim 9, characterized by using nanoclay additive (1) in the ratio of 0.5-1.5%.
Rigid polyurethane production method according to claim 1, characterized by using methyl diisocyanate (MDI) (5) as isocyanate.
Rigid polyurethane production method according to claim 1, characterized by using MDI (5):nanoclay additive (1) in the ratio of 100:1 to 100:3.
Rigid polyurethane production method according to claim 1, characterized by using as the blowing gas, high-purity cyclopentane or isobuthane/cyclopentane mixture.
Rigid polyurethane production method according to claim 1, characterized by using amine based catalyst/catalysts (10).
Rigid polyurethane production method according to claim 15, characterized by using as catalyst (10) the combinations of: Bis(2-dimethylaminoethyl)(methyl)amine (C9H23N3 based), Cyclohexyldimethylamine (C8H17N based) and N,N,N',N',N'',N''-Hexamethyl-1,3,5-triazine-1,3,5(2H,4H,6H)-tripropanamine (C18H42N6).
Rigid polyurethane production method according to claim 16, characterized by using following catalysts (10) whose proportions to each other are in the range of 1.50:1:0.5 - 1.75:1:0.8 : Bis(2-dimethylaminoethyl)(methyl)amine (C9H23N3 based), Cyclohexyldimethylamine (C8H17N based) and N,N,N',N',N'',N''-Hexamethyl-1,3,5-triazine-1,3,5(2H,4H,6H)-tripropanamine (C18H42N6).
Rigid polyurethane foam produced according to the method of claim 1, characterized by the isocyanate compounded with nanoclay modified with alkali added acid, comprising blowing gas and formulated polyol consisting of polyol (8), catalyst (10), surfactant (9), and pure water (11).
Rigid polyurethane foam according to claim 18, characterized by formulated polyol in the ratio of 35-45 % by weight, isocyanate compounded with nanoclay modified with alkali added acid in the ratio of 30-60 % by weight, and blowing gas in the ratio of 4-6 % by weight.
Rigid polyurethane foam according to claim 18, characterized by the formulated polyol comprising polyol (8) in the ratio of 90-99 % by weight, surfactant (9) in the ratio of 0.3-0.5 % by weight, catalyst (10) in the ratio of 0.1-0.2 % by weight and pure water (11) in the ratio of 0.3-0.5 % by weight.
Rigid polyurethane foam according to claim 18, characterized by the formulated polyol being polyether based.
Rigid polyurethane foam according to claim 18, characterized by the isocyanate being compounded with nanoclay modified with sodium (Na) added acid.
Rigid polyurethane foam according to claim 18, characterized by the nanoclay additive (1) being inorganic clay materials such as montmorillonite, vermiculite, kaolinite, talk, halloysite or sepiolite.
Rigid polyurethane foam according to claim 23, characterized by the nanoclay additive (1) being halloysite.
Rigid polyurethane foam according to claim 23, characterized by the nanoclay additive (1) being in the ratio of 0.5-1.5 % by weight.
Rigid polyurethane foam according to claim 18, characterized by the isocyanate being methyl diisocyanate (MDI) (5).
Rigid polyurethane foam according to claim 18, characterized by the blowing gas being high-purity cyclopentane or isobuthane/cyclopentane mixture.
Rigid polyurethane foam according to claim 18, characterized by the catalyst/catalysts (10) being amine based catalyst/catalysts (10).
Rigid polyurethane foam according to claim 18, characterized by the catalyst/catalysts (10) being the combinations of Bis(2-dimethylaminoethyl)(methyl)amine (C9H23N3 based), Cyclohexyldimethylamine (C8H17N based) and N,N,N',N',N'',N''-Hexamethyl-1,3,5-triazine-1,3,5(2H,4H,6H)-tripropanamine (C18H42N6).
Rigid polyurethane foam according to claim 29, characterized by the proportions of the catalyst/catalysts (10) to each other being in the range of 1.50:1:0.5 - 1.75:1:0.8.
Cooler characterized by comprising as insulation material the rigid polyurethane foam according to claim 18.