JP2001150558A - Method for manufacturing glass fiber-reinforced rigid polyurethane foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a glass fiber-reinforced rigid polyurethane foam which requires no surplus raw material because the height of the end parts in the width direction is not large and shows the capability to reduce the volume of waste and also a high uniformity of a glass fiber density near the end parts. SOLUTION: This method for manufacturing a glass fiber-reinforced rigid polyurethane foam comprises an underside material supply process to supply an underside material, a glass fiber mat supply process to supply a glass fiber mat to the surface of the underside material, a stock solution supply process to supply a rigid polyurethane foam foaming stock solution to the glass fiber mat and impregnate the latter with the former and a foaming process to cause the foaming stock solution to chemically react and foam to manufacture the glass fiber-reinforced rigid polyurethane foam. In addition, this method includes a glass fiber dispersion process to increase the thickness of the glass fiber mat.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a rigid polyurethane foam reinforced with glass fibers,
Specifically, production of glass fiber reinforced rigid polyurethane foam which can be used as a heat insulation panel for ultra-low temperature, especially a heat insulation panel suitable for heat insulation of a storage facility for storing substances having a low boiling point such as LNG, liquefied helium, liquefied nitrogen and the like, particularly LNG. About the method.

[0002]

2. Description of the Related Art A rigid polyurethane foam (hereinafter sometimes abbreviated as RPUF) mainly used as a heat insulating material for ultra-low temperature, which is reinforced by adding glass fiber, is provided with a glass fiber mat placed on a lower surface material and a rigid polyurethane foam. It is manufactured by a method in which a polyurethane foam foaming stock solution is supplied and impregnated, and then an upper surface material is supplied, followed by nipping with a nip roll, reaction and foaming.

At this time, a glass fiber mat having a width larger than the supply width of the rigid polyurethane foam foaming solution is used so that the glass fibers spread to the end in the width direction of the foam, and only the glass fiber mat protrudes. Glass fiber reinforced rigid polyurethane foam is manufactured.

[0004]

The glass fiber mat is
The constituent fibers are lifted by the increase in the liquid viscosity with the progress of the polymerization reaction of the RPUF foaming stock solution, and the thickness increases with foaming to form a glass fiber-reinforced rigid polyurethane foam having a uniform glass fiber density. The glass fiber mat which protruded from the end portion is shown in FIG.
During foaming, as shown in the state after foaming, it hangs down due to its own weight. Due to such factors as sagging of the glass fiber and a decrease in the expansion ratio of the rigid polyurethane foam at the end, the conventional glass fiber reinforced rigid polyurethane foam as a product has a so-called shoulder in which the height of the end in the width direction is reduced. Cause a falling phenomenon. Therefore, in order to cut out a board of a predetermined size from the obtained glass fiber reinforced rigid polyurethane foam (portion indicated as “predetermined dimension” in FIG. 4), it is necessary to take an extra width at the time of foaming. At the same time as the need arises, there is a problem in that the cut end (the portion indicated as "loss" in FIG. 4) must be discarded, so that the amount of waste increases. There is also a problem that the uniformity of the glass fiber density near the end of the obtained glass fiber reinforced rigid polyurethane foam is reduced.

An object of the present invention is to provide a board of a predetermined size without reducing the height of the end in the width direction, so that no extra raw material is required and the waste can be reduced. An object of the present invention is to provide a method for producing a glass fiber-reinforced rigid polyurethane foam having a high uniformity of glass fiber density near the end.

[0006]

According to the present invention, there is provided a method for producing a glass fiber reinforced rigid polyurethane foam, comprising: a lower surface material supplying step for supplying a lower surface material; a glass fiber mat supplying step for supplying a glass fiber mat on the lower surface material; Production of a glass fiber reinforced rigid polyurethane foam having a stock solution supplying step of supplying a stock solution of a rigid polyurethane foam to the glass fiber mat, and a foaming step of reacting and foaming the stock solution of the rigid polyurethane foam to produce a glass fiber reinforced rigid polyurethane foam The method is characterized in that it has a glass fiber dispersion step of raising the end of the glass fiber mat to a predetermined height to make the distribution of the glass fibers uniform.

[0007] By providing a glass fiber dispersion step of raising the end of the glass fiber mat and uniformly dispersing the glass fibers in the glass fiber reinforced rigid polyurethane foam as described above, if the height of the width direction end is low, And a board of a predetermined size can be obtained, so that no extra raw material is required, and the number of edges to be cut and discarded is very small, thereby reducing waste and reducing the glass fiber density near the edges. A glass fiber reinforced rigid polyurethane foam having high uniformity can be obtained.

[0008] The glass fiber dispersion operation for lifting the end of the glass fiber mat may be performed before the supply of the RPUF foaming stock solution. It is possible to obtain a glass fiber reinforced rigid polyurethane foam having a high hardness, which is preferable.

It is preferable that the lifting of the end is substantially the same as the lifting speed of the glass fiber inside, that is, the foaming rising speed of the RPUF, because the uniformity is improved.

[0010] The foaming of RPUF may be free foaming without providing a face material on the upper surface, or a method of providing an upper material as described below.

In the present invention, after the undiluted solution supply step, there is provided an upper surface material supply step of further supplying the upper surface material to form a sandwich form, and the glass fiber dispersion step is provided after the upper surface material supply step. Is preferred.

When the RPUF is foamed and cured, the face material itself adheres, and a glass fiber reinforced rigid polyurethane foam having the face material integrated can be obtained without providing a separate bonding step. It should be noted that the use of an air-permeable face material as the top material does not generate a share line, which is a low density layer generated near the interface between the RPUF and the face material, and the face material and the RPUF
A product having high adhesive strength is obtained, which is particularly suitable.

[0013] It is a preferable embodiment that a nip step is further provided between the upper surface material supply step and the foaming step.

In the nip process, a compressive force is applied to the upper surface material and the lower surface material, and the glass fiber mat and the RPU
This is a step of giving an extremely strong force to the F foaming stock solution, which allows the liquid and the glass fiber to blend into each other, and has the effects of improving the adhesive strength between the RPUF and the glass fiber, preventing the generation of air voids, and the like.

In the present invention, it is preferable to further provide a curing step of performing a curing reaction under a predetermined thickness under pressure.

By providing such a process, a glass fiber-reinforced rigid polyurethane foam having high thickness accuracy can be obtained in one process.

As a method for producing the glass fiber-reinforced rigid polyurethane foam of the present invention, the following steps are exemplified as preferred. (1) The glass fiber mat supply step, the stock solution supply step, and the foaming step are performed in a continuous line.
A method in which cutting is performed before the foaming / curing reaction is completed, and pressure is applied by a pressing means such as a press having a thickness defining means such as a spacer having a predetermined thickness. (2) The glass fiber mat supply step, the stock solution supply step, and the foaming step are performed using a double conveyor provided with a thickness regulating means such as a spacer at both ends, foamed and hardened to a predetermined thickness, and a predetermined length if necessary. After the cutting, a method of pressing with a pressing means such as a press having a thickness defining means is used. (3) A glass fiber mat is cut and laid as required in a mold having a predetermined panel size, a top material is supplied after supplying a rigid polyurethane foam foam solution, and a press is performed after nipping as necessary. Method of foaming and curing under thickness-regulated conditions. In any of the above methods, a glass fiber dispersion step is provided.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a schematic configuration of a manufacturing apparatus suitable for carrying out the present invention. Specifically, the continuous foaming-cutting-pressing step described in (1) of the above-mentioned manufacturing method. 1 shows an example by a manufacturing method having the following. In this example, a method for producing a glass fiber reinforced rigid polyurethane foam using flexible facing materials for both upper and lower surfaces is described.

The lower surface material 11L is supplied from the lower surface material supply device 10L onto the conveyors 7 and 8, on which a glass fiber mat 9 as a reinforcing glass fiber material is continuously rewound from the raw material and supplied and placed. After the rigid polyurethane foam undiluted solution M supplied from the head 3 of the foaming machine is supplied by the casting method, the upper surface material 11U is continuously supplied from the upper portion from the upper surface material supply device 10L to form a sandwich, and the nip roll is formed. After the glass fiber mat is sufficiently impregnated with the rigid polyurethane foam foaming stock solution by 13, it is sent to a heating oven 19 equipped with double conveyors 17 </ b> U and 17 </ b> L, and foamed and cured to produce a glass fiber reinforced rigid polyurethane foam B.

Numeral 20 denotes a glass fiber dispersion means for lifting the end of the glass fiber mat.
(A) schematically shows this. The glass fiber dispersion means 20 includes:
A plurality of clips 22 are provided, a part of the end portion of the glass fiber mat G is gripped, and the clip is raised in response to expansion in the height direction due to foaming of the rigid polyurethane foam foaming stock solution. Lift. FIG.
FIG. 2B shows a state immediately after the supply of the rigid polyurethane foam foaming liquid. At this stage, the clip 22 is at the lower position and moves to the state shown in FIG. The rise of the clip due to the foaming of the rigid polyurethane foam foaming solution is faster as the upper layer grasps the glass fiber,
It is set so that the lower the glass fiber of the lower layer is, the more slowly it rises.

The glass fiber dispersing means 20 is shown in FIG. 2 as an example in which three clips 22 are provided in the height direction, but the number is not particularly limited. Also,
When using a heavy-weight surface material such as wood plywood as the upper surface material, it is a preferable embodiment to provide a means for lifting the surface material.

A plurality of clips 22 are provided in series in the flow direction of foam production, and return from the state of FIG. 2A to the position of FIG. 2B in a circulating state such as a caterpillar system. Preferably, it is configured.

The clip 22 does not need to hold the glass fiber G until the foaming reaction is completely completed. If the polymerization reaction proceeds to some extent and the foam strength is developed, the clip 22 may be released. I don't care.

A known method can be used for the up / down and up / down mechanism of the clip in the glass fiber dispersing means 20, such as a hydraulic cylinder, an air cylinder, a combination of a chain and a gear, and a combination of a timing belt and a gear. Is done.

In the example shown in FIG. 2, the glass fibers are layered, but need not be completely layered, and the layer held by the clip 22 has a high glass fiber density, and the other portions have a lower glass fiber density. It is more preferable that the glass fibers are dispersed at a glass fiber density, that is, the glass fibers are more uniformly dispersed in the rigid polyurethane foam.

The type of the clip 22 is not particularly limited, and means for gripping or hooking a glass fiber such as a clip or a hook are exemplified.

[0028] The curing step is the RPUF immediately after the completion of the foaming step.
Is a step of maintaining the pressure to a predetermined thickness. Since the reaction of RPUF proceeds somewhat even after the end of the foaming step and causes a change in thickness, it is possible to obtain a glass fiber-reinforced rigid polyurethane foam having a high dimensional accuracy in thickness by completing the reaction while maintaining the predetermined thickness. it can. The curing step can be performed by, for example, a method of inserting a product between platens of a hot press provided with a predetermined spacer and applying pressure.

FIG. 3 shows a preferred example of an apparatus used in the curing step. As the pressurizing device 30, for example, a press having a plurality of bases 33 and a hydraulic cylinder S is used. The board B of the glass fiber reinforced rigid polyurethane foam manufactured in FIG. 1 is cut into an appropriate length and placed between the platens. Spacers 31 for securing a predetermined space are provided between the surface plates. The entire press machine may be installed in a temperature control room such as an oven, or the platen may be a hot plate that can be heated.

The spacer 31 may be a frame formed so as to surround the panel, or may be provided only at both ends in the length direction or the width direction. Further, the spacer 31 may be a continuous one-piece type or a block type. When the glass fiber dispersing means is a continuous one-piece type, it is possible to provide an appropriate slit to act on the glass fiber mat.

In the manufacturing method using the frame described in (3) above, the frame defines all of the outer shape of the product panel.

RPUF is formed using a known rigid polyurethane foam stock solution having excellent low-temperature insulation performance.
The rigid polyurethane foam stock solution is a component (polyol component) containing an active hydrogen-containing compound, a foaming agent, a catalyst, and the like.
And a component having a polyisocyanate compound as a main component (isocyanate component). The polyol component and the isocyanate component are mixed using a foaming machine, and the mixture is subjected to molding of a heat insulating panel as a foaming stock solution composition.

As the polyisocyanate compound constituting the isocyanate component, any di- or polyisocyanate compound known in the technical field of polyurethane can be used, and specific examples include the following compounds.

Aromatic diisocyanate compounds such as 4,4'-diphenylmethane diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, naphthalene diisocyanate, and aliphatic diisocyanates such as 1,6-hexamethylene diisocyanate (HDI) , Isophorone diisocyanate (IPD
I), hydrogenated m-xylylene diisocyanate (HX
DI), alicyclic diisocyanates such as norbornane diisocyanate, crude MDI (44V-10,44
V-20 etc. (manufactured by Bayer AG)), M containing uretonimine
Examples include polyfunctional isocyanates such as DI (liquid MDI) (Millionate MTL; manufactured by Nippon Polyurethane Industry).

The above polyisocyanate compounds may be used alone or in combination of two or more. Among the above polyisocyanate compounds, Crude MD is used because of its ease of handling, speed of reaction, excellent physical properties of RPUF obtained, and low cost.
The use of I is most preferred.

As the active hydrogen group-containing compound which is the main component of the polyol component, a compound generally known as a polyol compound can be used. Particularly, as polyols for rigid polyurethane foams, aliphatic polyols, aromatic polyols, amine polyols and the like exemplified below are known.

An aliphatic polyol polyfunctional active hydrogen compound, that is, an aliphatic or alicyclic polyfunctional active hydrogen compound as a polyol initiator, an alkylene oxide, specifically, propylene oxide (P
O), cyclic ethers such as ethylene oxide (EO), styrene oxide (SO), and tetrahydrofuran.
Polyfunctional oligomers obtained by ring-opening addition polymerization of one or more species are exemplified.

Examples of the polyol initiator include glycols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol and neopentyl glycol, trimethylolpropane, glycerin and the like. And trifunctional alcohols such as pentaerythritol, polyhydric alcohols such as sorbitol and sucrose, and water.

Instead of the alkylene oxide, or together with the alkylene oxide, a polyol compound obtained by ring-opening polymerization of a lactone such as ε-caprolactone can be used.

Amine-based polyol As a polyol initiator, a primary or secondary amine is used as an alkylene oxide, specifically one or more of propylene oxide (PO), ethylene oxide (EO), styrene oxide (SO), tetrahydrofuran and the like. Is a polyfunctional polyol compound obtained by ring-opening addition polymerization of

Examples of the initiator include amines such as ethylenediamine, toluenediamine and diphenylmethanediamine, and alkanolamines such as monoethanolamine and diethanolamine.

Aromatic polyol Examples of the method include adding the above-described alkylene oxide to a polyfunctional active hydrogen compound having an aromatic ring in the molecule, and an ester of an aromatic polycarboxylic acid and a polyhydric alcohol.

Examples of the polyol compound obtained by adding the above-mentioned alkylene oxide to a polyfunctional active hydrogen compound include hydroquinone, bisphenol A, etc.
Compounds obtained by ring-opening addition of at least one of O and SO are specifically exemplified.

Specific examples of the ester of an aromatic polycarboxylic acid and a polyhydric alcohol include ester polyols at the hydroxyl group end of terephthalic acid, phthalic acid, isophthalic acid and the like with ethylene glycol and diethylene glycol.

The above polyol compound has a hydroxyl value of 2
It is preferable that the average number of functional groups is 2 to 6 at 00 to 600 mgKOH / g.

The above polyol compounds may be used alone or in combination of two or more to form RPUF having more preferable characteristics.

In producing the rigid polyurethane foam of the present invention, a catalyst, a flame retardant, a foaming agent, a coloring agent, an antioxidant and the like well known to those skilled in the art can be used.

As the foaming agent, a chlorofluorocarbon compound having a small ozone depletion coefficient, for example, HCFC-141b, HFC-
134a, fluorine-containing compounds such as HFC-245fa,
Aliphatic or alicyclic hydrocarbons such as cyclopentane and n-pentane, and other water can be used without limitation. In particular, use of HCFC-141b is preferred because of its excellent low-temperature insulation performance.

As a catalyst, triethylenediamine, N
-Methylmorpholine, N, N, N ', N'-hexamethylethylenediamine, tertiary amines such as DBU, and metal catalysts such as dibutyltin dilaurate, dibutyltin diacetate and tin octylate as urethanization reaction catalysts Is exemplified. When water is used as one component of the blowing agent, the use of a tertiary amine catalyst is preferred because the organotin-based catalyst is hydrolyzed and deteriorated.

It is also preferable to use a catalyst that forms an isocyanurate bond that contributes to the improvement of flame retardancy in the structure of the polyurethane molecule. Examples thereof include potassium acetate and potassium octylate. Some of the above tertiary amine catalysts also promote the isocyanurate ring formation reaction. A catalyst that promotes isocyanurate bond formation and a catalyst that promotes urethane bond formation may be used in combination.

In the present invention, it is also a preferred embodiment to further add a flame retardant.
Examples include metal compounds such as halogen-containing compounds, organic phosphates, antimony trioxide, and aluminum hydroxide.

However, in these flame retardants, for example, when an organic phosphoric acid ester is excessively added, the physical properties of the obtained rigid polyurethane foam may deteriorate, and when a metal compound powder such as antimony trioxide is excessively added. This may cause problems such as affecting the foaming behavior of the foam, and the amount of addition is limited to a range that does not cause such problems.

The rigid polyurethane foam of the present invention comprises
It is preferable to use a plasticizer as needed. Such plasticizers also preferably contribute to flame retardancy, and halogenated alkyl esters of phosphoric acid, alkyl phosphates, aryl phosphates, phosphonates, and the like can be used. Specifically, tris ( β-chloroethyl) phosphate (TCEP, manufactured by Daihachi Chemical),
Tris (β-chloropropyl) phosphate (TMCP
P, manufactured by Daihachi Chemical Co., Ltd.), tributyl phosphate, triethyl phosphate, cresyl phenyl phosphate, dimethyl methyl phosphonate and the like, and one or more of these can be used. The added amount of the plasticizer is preferably 5 to 30 parts by weight based on 100 parts by weight of the polyol component. If the ratio exceeds this range, problems may occur such that a sufficient plasticizing effect cannot be obtained or physical properties of the foam deteriorate.

As the stock solution for forming the rigid polyurethane foam, a commercially available stock solution using a component selected from the above-mentioned components can be used. Specifically, Sofran R115-90F, Sofran R 115-90H (Manufactured by Toyo Tire & Rubber Co., Ltd.).

The glass fiber material used to reinforce the RPUF is preferably a glass fiber having a large aspect ratio. As a suitable material, a mat-like product of long glass fiber, specifically, a chop strand mat, continuous A strand mat or the like is exemplified. The use of a continuous strand mat is most preferable because of its excellent impregnating properties of the RPUF foaming stock solution and foam reinforcing properties.

As the face material used in the present invention, well-known face materials such as a flexible face material and a high-rigidity face material can be used without limitation. Among these, it is preferable to use a gas-permeable surface material as described above as the upper surface material.

Specific examples of the highly rigid air-permeable plate-like material include gypsum board, wood plywood, calcium silicate board and the like. Physical strength and reactive adhesive strength with a rigid polyurethane foam are given. The use of wood plywood is most preferred because it is good and has low thermal conductivity. The configuration, size, and the like of the wood plywood are not particularly limited as long as the rigidity meets the purpose. Generally, the thickness commercially available as architectural plywood is 8 to 20 mm, preferably 9 to
The use of 12 mm plywood is also cost effective. Examples of the flexible surface material include a paper surface material, a resin-laminated paper surface material, an aluminum sheet, a steel plate, a known flexible surface material such as a resin film, and the like, and can be used without limitation, but the physical strength of the sheet itself is not limited. Aluminum sheet, glass cloth, resin coating layer, because it is good and does not corrode even if dew condensation water is generated when used for high heat insulation applications, and has good reactive adhesive strength with rigid polyurethane foam Most preferred is the use of a composite material with As such a composite material, a surface material in which a resin layer containing a glass cloth is laminated on both surfaces of an aluminum sheet (for example, trade name: HTRCHINS
ON Company) and Trigit (manufactured by Unitika Ltd.) are particularly preferred. Since such an aluminum sheet composite face material has no permeability to an organic compound, a glass fiber reinforced rigid polyurethane foam obtained by using the aluminum sheet composite face material is particularly suitable as a heat insulating material for an LNG storage tank.

When a releasable face material such as release paper or a release film is used, the skin surface of the glass fiber reinforced polyurethane foam formed by peeling off the releasable face material is replaced with another rigid polyurethane foam. It becomes possible to adhere.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing an apparatus for producing a glass fiber-reinforced rigid polyurethane foam of the present invention.

FIG. 2 is a view showing a cross section taken along line XX in FIG.

FIG. 3 is a side view showing an example of an apparatus suitable for use in a curing step.

FIG. 4 is a schematic view showing the state of a foaming stage in the production of a glass fiber-reinforced rigid polyurethane foam according to the prior art.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kazuhiko Kamezaki, 1-2-1, Marunouchi, Chiyoda-ku, Tokyo, Japan Nihon Kokan Co., Ltd. (72) Yasuo Komatsu 1-2-1, Marunouchi, Chiyoda-ku, Tokyo, Japan (72) Inventor Takeshi Inoue 1-17-18 Edobori, Nishi-ku, Osaka-shi, Osaka Toyo Tire & Rubber Co., Ltd. (72) Inventor Motoya 1-17-18 Edobori, Nishi-ku, Osaka-shi, Osaka Toyo Rubber Industry Co., Ltd. (72) Inventor Ishino Politics 1-17-18 Edobori, Nishi-ku, Osaka-shi, Osaka Toyo Rubber Industries Co., Ltd. F-term (reference) in Rubber Industry Co., Ltd. 4F072 AA01 AA07 AB09 AB29 AD43 AG15 AG16 AG18 AG22 AH12 AH13 AH16 AH20 AH25 AK18 AL09 4F205 AA42 AD16 AD17 AG01 AG20 HA15 HA29 HA33 HA37 HA43 HB02 HC06 HC16 HF05 HK02 HK03 HK04 HK05 HK12 HM06

Claims (4)

[Claims] A bottom material supply step of supplying a bottom material; a glass fiber mat supply step of supplying a glass fiber mat on the bottom material; a stock solution supply step of supplying a rigid polyurethane foam foaming stock solution to the glass fiber mat; A method for producing a glass fiber reinforced rigid polyurethane foam having a foaming step of producing the glass fiber reinforced rigid polyurethane foam by reacting and foaming the rigid polyurethane foam foaming stock solution, wherein an end of the glass fiber mat is set at a predetermined height. A method for producing a glass fiber-reinforced rigid polyurethane foam, comprising a glass fiber dispersion step of lifting and uniformly dispersing glass fibers. 2. The method according to claim 1, further comprising, after the stock solution supplying step, an upper surface material supplying step of supplying an upper surface material to form a sandwich form, and the glass fiber dispersing step is provided after the upper material supplying step. Item 4. The method for producing a glass fiber reinforced rigid polyurethane foam according to item 1. 3. The method for producing a glass fiber reinforced rigid polyurethane foam according to claim 2, further comprising a nip step between the upper surface material supply step and the foaming step. 4. The method for producing a glass fiber reinforced rigid polyurethane foam according to claim 2, further comprising a curing step of performing a curing reaction under a predetermined thickness under pressure.