JPH0459839A - Polyol composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition for rigid urethane foams capable of performing in-place foaming under conventional execution conditions without using fluorocarbon foaming agents by containing water in a polyol component prepared by adding a polyester polyol to specific three kinds of polyether polyols. CONSTITUTION:The objective composition is obtained by containing 1-6 pts.wt. water in 100 pts.wt. polyol component composed of (A) 40-90wt.% blend of (i) a polyether polyol obtained by adding 6-12mol propylene oxide to 1mol ethylenediamine with (ii) a polyether polyol prepared by adding 4-8mol propylene oxide and 2-10mol ethylene oxide to 1mol ethylenediamine at (5:1) to (2:1) ratio, (B) 10-60wt.% polyether polyol obtained by adding an alkylene oxide to a low- molecular weight polyhydric alcohol and (C) 0-20wt.% polyester polyol. Furthermore, a foam stabilizer, a flame retardant, etc., are preferably contained in the aforementioned composition.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to polyol compositions for rigid urethane foams that do not contain fluorocarbon blowing agents.

Conventional technology The construction method for rigid urethane foam, which is widely used for preventing condensation, keeping warm, keeping cold, and insulating heat, is not only able to form a seamless heat insulating layer, but also allows for construction that follows the shape of the building structure. For these reasons, the mainstream method is to spray foam or injection foam the polyol component and isocyanate component at the construction site.

In this case, Freon is often used as a blowing agent because it has advantages such as low thermal conductivity, low boiling point, nonflammability, low toxicity, and ability to reduce the viscosity of the system.

However, in conjunction with the recent global environmental conservation movement, the problem of ozone layer depletion caused by fluorocarbon gas has suddenly come into focus, and there is a trend toward a complete ban on its use in the near future.

For this reason, unless an alternative foaming agent comparable to CFCs is developed, it will not be possible to foam rigid urethane foam on-site under the conventional construction conditions (foaming machine, construction temperature, reactivity, etc.). There is an urgent need to resolve this issue.

Problems to be Solved by the Invention In view of the above circumstances, this invention was made in order to enable on-site foaming of rigid urethane foam under conventional construction conditions without using fluorocarbon foaming agents. .

Means for Solving the Problems This invention provides (iXa) a polyether polyol to which 6 to 12 moles of propylene oxide are added per mole of ethylenediamine, and (b) 4 to 8 moles of propylene oxide and 2 moles of ethylene diamine per mole of ethylenediamine. Bi2-10 polyether polyol 40-90% by weight, (
ii) 10-60% by weight of polyether polyol obtained by adding alkylene oxide to low molecular weight polyhydric alcohol
and (iii) polyester polyol 0-20
The present invention relates to a polyol composition for rigid urethane foam, which contains 1 to 6 parts by weight of water per 100 parts by weight of the polyol component.

6 propylene oxide per mole of ethylenediamine
Among the polyether polyols (a) added with ~12 moles, particularly preferred polyols have a molecular weight of 450 to 800.
and has a viscosity of 500 to 5000 cps (25°C). A particularly preferred polyol (a) has a molecular weight of 6
00, Hyl'roxyl number 360m9KOH1 viscosity 2 0
00 cps (25°C).

Generally, when the molecular weight is less than 450, the viscosity increases and the hydroxyl value becomes high, making it difficult to formulate a spray.On the other hand, when the molecular weight is more than 800, foam shrinkage occurs.

4 to 4 propylene oxide per mole of ethylenediamine
Among the polyether polyols (b) to which 8 mol and 2 to 10 mol of ethylene oxide are added, a particularly preferred polyol is one in which 4 mol of propylene oxide is added per 1 mol of ethylenediamine, and then 10 mol of ethylene oxide is added; Or, after adding 5 mol of propylene oxide/dolo per 1 mol of ethylenediamine, a polyol to which 7 mol of ethylene oxide has been added (molecule j1
750, hydroxyl number 30019KOH1 viscosity 500
cps (25°C)).

Polyol (b) particularly contributes to improving reaction activity and lowering viscosity, but when the content of ethylene oxide is higher than the above-mentioned value, the reaction between water, hydroxyl groups, and NGOs, which will be explained below, is reduced. It becomes difficult to adjust the balance, that is, foaming and resinization, which not only causes cracks in the foam and the formation of open cells in the foam, but also makes it impossible to obtain green strength, resulting in thin margins and swelling due to concentration of gas. bring.

The ratio of polyether polyols (a) and (b) is not particularly limited, but is usually (a):(b)=5:l~2
: 1 (weight ratio).

The proportion of component (i) among the bool components used in the present invention is 40 to 90% by weight; if it is less than 40% by weight, it is difficult to control the reaction, and if it is more than 90% by weight, the foam strength cannot be obtained. I can't.

The polyether polyol (11) obtained by adding alkylene oxide to a low molecular weight polyhydric alcohol (c) polyhydric alcohols such as ethylene glycol, propylene glycol, pentyl glycol, hexylene glycol,
Examples include polyether polyols in which alkylene oxides such as ethylene oxide or propylene oxide are added to glycerin, trimethy0-luperopane, pentaerythritol, sorbitol, or sucrose.

A particularly preferred polyether polyol (ii) is a polyol obtained by adding propylene oxide to sucrose, propylene glycol or glycerin, and has an average number of functional groups of 3 or more and a molecular weight of 600 to 800.

The polyether polyol (ii) contributes to lowering the viscosity of the polyol composition and increasing the strength of the foam. .

The content of polyether polyol (+1) is 10 to 60
If it is less than 10% by weight, mechanical strength cannot be obtained and shrinkage tends to occur. 60% by weight
If it exceeds the above range, it becomes difficult to control the reaction, and the adhesive strength with the object to be sprayed tends to decrease.

Polyester polyol (iii) is used as desired, mainly to make the foam flame retardant and to make the cells finer, and its content is 0 to 20% by weight, and if it exceeds 20% by weight, Poor adhesion to objects is likely to occur due to foam shrinkage and flyability.

The polyester polyol (iii) is a polyester polyol (III) having a molecular weight of 300 to 300, which is obtained by adding an alkylene compound such as ethylene oxide and/or propylene oxide to an esterified product of an organic polybasic acid and a low molecular weight polyhydric alcohol.
1000 polyols are exemplified.

Examples of organic polybasic acids that can be used include saturated fatty acids such as adipic acid, phthalic acid, sebacic acid, and timer acid, unsaturated fatty acids, and aromatic acids.

Particularly preferred is adipic acid. Examples of the low molecular weight polyhydric alcohol that forms an ester bond with the organic polybasic acid include polyhydric alcohols such as diols, triols, and hexaols;
For example, ethylene glycol, propylene glycol,
Examples include butylene gelicol, diethylene glycol, dipropylene glycol, trimethylolpropane, glycerin, hexanetriol, and sorbitol.

The equivalent ratio of the organic polybasic acid to the low molecular weight polyhydric alcohol is preferably 1 to 1.5, particularly 1 to 1.3.

The average hydroxyl value of the polyol component consisting of the above polyols (i) to (mountain) is preferably 250 to 400x
9KOH, and the viscosity is usually 300 to 1000 cps (
25°C), and if the content of the ethylene oxide component becomes too high, it becomes difficult to balance the reaction.
Since cracks tend to occur, open cells tend to form, and mechanical strength tends to be insufficient, it is usually desirable to keep the content at about 20% or less.

The polyol composition for rigid urethane foam according to the present invention is characterized in that it does not contain a fluorocarbon blowing agent, unlike conventionally used polyol compositions of this type, but contains water.

During spray foaming, the water present in the polyol composition reacts with a portion of the incyanate component to generate CO and gas, which acts as a blowing agent. Therefore, in the present invention, the foam density, that is, the expansion ratio of the foam, is adjusted by adjusting the amount of water blended.

The amount of water blended is 1 to 6 parts by weight per 100 parts by weight of the above polyol component, and if it exceeds 6 parts by weight, it is necessary to lower the hydroxyl value of the polyol component or add components that do not participate in the reaction. (This is because there is a mechanical constraint that the polyol component and incyanate component must be fed at a volume ratio of 1=1), which causes foam shrinkage and poor adhesion. If it is too low, the foam density will increase and the amount of raw material used during spray construction will increase, which will increase costs and make it unsuitable for reality, and the thermal conductivity of the foam will increase significantly and the insulation performance will decrease.

By adjusting the amount of water blended as described above, a rigid urethane foam with a foam density of 25 to 80 and 9/rp'' can be obtained.

In addition to the above-mentioned polyol components (1) to (iii) and water, the polyol composition according to the present invention further contains conventional additives as appropriate.

Examples of such additives include foam stabilizers, flame retardants, reaction accelerators, and viscosity modifiers.

The amount of these additives to be added depends on the type of the additive, the viscosity and hydroxyl value of the polyol component, the type of incyanate component, etc., and is not particularly limited.
- For boat fishing, per 100 parts by weight of the polyol component, 0.5 to 2.5 parts by weight of a foam stabilizer, 0 to 50 parts by weight of a flame retardant, 0 to 91 to 5 parts by weight of a reaction accelerator, and 0 to 5 parts by weight of a viscosity modifier. 2
It is 0 parts by weight.

As the foam stabilizer, any of the common silicone foam stabilizers used in the production of polyurethane foam may be used.

As the flame retardant, halogen-containing phosphate ester compounds are desirable, such as tris(2,2-chloroethyl) phosphate, tris(2,2-chloropropyl) phosphate, tris(dichloropropyl) phosphate, ethylenebis(bischloroethyl) phosphate), polyoxyethylene bis(bischloroethyl phosphate), chloroethyl phosphate oligomer, and the like.

As a reaction accelerator, amine catalysts (e.g., triethanolamine, tetramethylhexamethylenediamine,
triethylenediamine, bis-2-(dimethylamino)ethyl ether, etc.), organometallic catalysts (e.g., dibutyltin dilaurate, stannous octylate, lead octenoate, etc.), and two or more of these may be used in combination as desired. You may.

As a viscosity modifier, polyoxyalkylene glycol dialkyl ether (molecular weight 94 to 600) that does not participate in the urethane formation reaction and does not reduce the strength of the foam is used.
For example, polyoxyethylene glycol dimethyl ether (molecular weight 300) +7) and alkylene carbonates such as propylene carbonate and ethylene carbonate are exemplified. There must be.

Furthermore, - plasticizers used in boat fishing, such as dioctyl phthalate, dioctyl adipate, tricresyl phosphate, etc., can also be used, but in this case they tend to reduce the mechanical strength of the foam. should be considered.

The above polyol composition according to the invention is subjected to in-situ foaming with polyisocyanates for rigid urethane foams.

Such polyisocyanates include 2°4-tolylene diisocyanate, 65/35) lylene diisocyanate, 80/20 tolylene diisocyanate, 4,4
Examples include diphenylmethane diisocyanate, metaxylylene diisocyanate, and polymethylene polyphenylinocyanate. Among the above-mentioned polyisocyanates, 4.4'-diphenylmethane diisocyanate, polymethylene polyphenylisocyanate, etc., which have a low vapor pressure in in-situ foaming, are particularly preferred because they have low toxicity (and reactivity) and are suitable for foam production.

Currently, typical in-situ spray foaming of rigid urethane foams is carried out under the following mechanical, temperature and raw material conditions; Enables on-site spray foaming in the range = (1) Mechanical conditions: Use of the conventional on-site foaming machine (ii) Temperature conditions: Raw material temperature (in the storage container): 0 to +
30''C, raw material temperature at gun tip discharge: +30 to +50℃, body temperature knee 10'C to +40℃ (iii) Raw material conditions: Volume ratio of polyol component to isocyanate component = lOO: 100 Viscosity of polyol component: 100 ~300 cps (20°C), viscosity of incyanate component: 100-200 cps (25°C), curing time = 5-15 seconds or less.The present invention will be illustrated by examples.

Example 1 A polyol composition was prepared according to the following formulation.

Ingredients Compounding amount (parts by weight) Polyol 11) 50 Polyol ■ 2) 20 Polyol II [3) 20 Polyol IIV 4) 10 Foam stabilizer (silicone oil) 2 Flame retardant (orthophosphoric acid ester) 30 Reaction accelerator ■ 5) 2 Reaction accelerator n6) l water
4.5 Viscosity modifier 7) 5 1) 85% propylene oxide to 1 mole of ethylenediamine
Polyether polyol subjected to molar addition polymerization [molecular weight:
560, active hydrogen number = 4, viscosity: 3000 cps
(25℃) 2) Add 4 moles of propylene oxide to 1 mole of ethylenediamine, and then add 10 mols of ethylene oxide.
Polyether polyol with molar addition [molecular weight = 75
0, active hydrogen number: 4, viscosity: 500 cps (25°C)] 3) Polyether polyol obtained by addition polymerizing propylene oxide to sucrose and propylene glycol [molecular precious 800, active hydrogen number: 3°5, viscosity: 250 cps
(25℃) 4) Polyester polyol made by addition polymerizing propylene oxide and ethylene oxide to polyester made by condensing 1 mole of phthalic anhydride with diethylene glycol and ethylene glycol [molecular weight: 360, viscosity 1100 cps
(25°C)] 5) Tertiary amine catalyst 6) Dibutyltin dilaurate 7) Polyoxyethylene glycol dimethyl ether [
Molecular weight: 300, viscosity: 9.5 cps, (25°C
)] Obtained polyol composition [Viscosity: 300 cp
s (25°C)] 100 parts by volume and diphenylmethane diisocyanate crude product (NGO index: 1.1
0) 110 parts by volume was spray-foamed using a Gasmer FF foaming machine under the following conditions, and the workability was good and no inferior to that when a conventional fluorocarbon-containing polyol composition was used.

Target object: Asbestos slate board (vertical surface) Target object temperature: 15℃ Ambient temperature: 20℃ Cream type: 1-2 seconds Rise Timeco 8-10 seconds Free density: 33 to 9/w3 Spraying thickness: 25xm Above spray Compliant with foam, veneer plywood (6x shoulder thickness)
A spray foam was formed on the spray foam to a thickness of 100 gg, and various properties of the spray foam were examined, and the results are shown in Table 1 below.

Table-1 1) JISA 2) JISA 3) ASTM 4) ASTM 5) ASTM Effects of the Invention By using the polyol composition according to the present invention,
Without using CFC foaming agents, whose use is in the direction of being completely banned from the perspective of environmental conservation, we can achieve the desired results within the permissible range of mechanical, temperature, and raw material conditions conventionally used for on-site spray foaming of rigid urethane foam. On-site spray foaming is possible.

Therefore, by using the polyol composition according to the present invention, for example, the following effects can be obtained: (i) Good adhesion between the urethane foam and the building block, no peeling, and a stable circular spray pattern. becomes.

(ii) No sutures or cracks occur in the constructed foam, and the foam density is the same as that of conventional products (30
~100 to 9/x3).

(iii) The insulation performance is better than other insulation materials (e.g. glass wool, expanded styrene, etc.) (0 at 0℃,
022 K cal/mhr"c or less).

(iv) A closed cell foam is formed and has excellent mechanical strength and dimensional stability.

(v) There is no generation of odors or toxic gases, and the working environment during construction can be kept stable.

(vl) The on-site foaming machine that has been commonly used can be used as is.

Claims (1)

[Claims] 1. (i) (a) A polyether polyol to which 6 to 12 moles of propylene oxide are added per mole of ethylenediamine, and (b) 4 to 8 moles of propylene oxide and 2 to 1 mole of ethylene oxide per mole of ethylenediamine.
Polyether polyol with 0 mol added 40-90
Weight %, (ii) polyether polyol 10 to 6 with alkylene oxide added to low molecular weight polyhydric alcohol
0% by weight and (iii) polyester polyol 0~
A polyol composition for rigid urethane foam, characterized in that it contains 1 to 6 parts by weight of water per 100 parts by weight of a 20% by weight polyol component. 2. Foam stabilizer 0.5 per 100 parts by weight of polyol component
~2.5 parts by weight, flame retardant 0-50 parts by weight, reaction accelerator 0
．． The polyol composition according to claim 1, containing 1 to 5 parts by weight and 0 to 20 parts by weight of a viscosity modifier.