JPH02202509A - Fiber-reinforced polyurethane resin composition having excellent low-temperature quick curability - Google Patents

Abstract

PURPOSE:To obtain the subject quick-curing composition giving a molded article having excellent impact resistance, heat-resistance, etc., by combining a polyurethane resin composition having a specific composition and containing a specific urethanization catalyst with a long-fiber mat at a specific ratio. CONSTITUTION:The objective composition contains (I) a polyurethane resin composition composed of (A) an organic polyisocyanate, (B) a polyether polyol having a molecular weight of 300-700 and containing >=3 functional groups, (C) ethylene glycol and/or 1,3-butanediol as a chain extender and (D) an imidazole compound of formula (m and n are 1-4) as a curing catalyst at a weight ratio [A/(B+C)] of (130 to 180)/100 and (II) a long-fiber mat at a weight ratio (I/II) of 90/10 to 50/50. The compound of formula is e,g. 1,2- dimethylimidazole.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention has fast curing properties that can be cured in 1 to 3 minutes in a temperature range of 40 to 60°C, and the cured product has good impact resistance and heat resistance. ,
This invention relates to a fiber-reinforced polyurethane composition with excellent rigidity.

[Conventional technology]

In recent years, prices have become cheaper in the field of auto parts.

And with the diversification of designs, the use of plastic is increasing. In particular, as structural members and semi-structural members, long fiber reinforcement and plasticization with high rigidity are being sought.

Conventionally, unsaturated polyester resins have been the mainstream as this type of resin. Sheet molding compound (SMC) is a method for producing this type of resin with high efficiency.
However, it requires high temperature and high pressure, and requires a large investment in equipment.In addition, fibrous reinforcing material is set in the mold in advance, and after the mold is closed, the liquid unsaturated polyester resin composition is A resin injection method is also known, in which resin is injected and cured within the mold, but curing is usually slow.

Production efficiency is low. In general, this type of resin has poor impact resistance.

On the other hand, polyurethane resins are known to provide cured resins with good impact resistance.

Generally has poor heat resistance. Therefore, in order to improve heat resistance,
There is a method of increasing crosslinking density using a polyfunctional polyol, but in this case, gelation is accelerated, but the reaction rate immediately after curing is low and unreacted isocyanate groups and hydroxyl groups tend to remain.
Second, the development of physical properties is slow,9 and it is dangerous to obtain physical properties that can withstand practical use after a few days have passed. The urethane composition thickens too quickly, and the urethane composition does not fully penetrate into the long fiber mat, causing it to harden.

On the other hand, the reaction v! allows the liquid to penetrate into the long fiber mat! 4g
When M is used, there is a problem that the development of physical properties during curing is poor, demolding takes a long time, and productivity is low.

[Problems that the invention attempts to solve]

The present invention provides a fiber-reinforced polyurethane resin composition that has good permeability into long-fiber mats, exhibits excellent physical property development through low-temperature rapid curing, and (1) exhibits excellent impact resistance and heat resistance when cured. That's true.

(Next Means for Solving the Problems) As a result of extensive research, the present inventors have discovered that a combination of a specific urethane composition, a specific catalyst, and a long fiber mat can improve low-temperature, rapid curing properties.

It was discovered that the physical properties of the molded article were excellent, leading to the present invention.

That is, the present invention provides a fiber-reinforced polyurethane resin composition consisting of a long fiber mat and a polyurethane resin, in which the polyurethane resin contains a preorganic polyiso7anate b8, a polyether polyol c having a molecular weight of 300 to 700, and having 3 or more functional groups, ethylene glycol, and / or 1,3-butanediol d, c, H, consisting of an imidazole compound represented by the general formula tl) as a curing catalyst.

(m = 1 to 4. n = integer of 1 to 4) The ratio of a and bee is 130 / 100 to 180 /
100 weight ratio, and the ratio of the polyurethane resin composition to the long fiber mat is 90/10 to 50,150 weight ratio.

Is this composition pre-molded? Molding can be carried out by setting a ζ-long fiber mat and injecting the polyurethane resin composition after closing the mold, or by injecting the polyurethane resin composition while the mold is closed, depending on the structure of the mold.

Injection is conveniently carried out using a high-pressure reaction injection molding machine (RIM) or a two-liquid mixing low-pressure injection machine.

Organic polyiso7ane that can be used in the present invention)
As t-1, primary aliphatic polyisocyanates include hexamethylene-1,6-diincyanate, 2,2.4-1 and 42.4.4-trimethylhexamethylene-1,6-diisocyanate. etc.; As alicyclic polyisocyanates, the following toeha, cyclohexane-1
, 4'-diisocyanate, dicyclohexylmethane-
4,4-diisocyanate, etc.; examples of aromatic polyisocyanates include P-phenylene diincyanate and tolylene-2,4-1-2,6-diincyanate.

diphenylmethane-2,4-1st-4,4'-diincyanate, naphthylene-1,5-diisocyanate,
These include xylylene-1,3- or -1,4-diincyanate, diphenyl ether-4,4'-diisocyanate, and the like.

In addition, polyphenylene/polymethylene polyisocyanates of the type obtained by condensing aniso/ and formalin and then phosgenation, diphenylmethane diisocyanates which are liquid at room temperature and have a carbodiimide group or uretonimine group, or urethane/bonds, allophanate bonds, Modified polyisocyanates containing biuret linkages, uretidi 73jl, and the like can also be used.

Also, an isocyanate-based prepolymer obtained by reacting polyols with an excessive amount of the polyisocyanate can also be used.

Among these, particularly preferred are organic polyisocyanates,
Diphenylmethane diisocyanate-based polyisocyanates include polyphenylene polymethylene polyisocyanate, which is liquid at room temperature, provides low viscosity, and highly rigid molded products, or diphenylmethane diisocyanate having a carbodiimide group or uretonimine group.

Examples of the polyether polyol (h) that can be used in the present invention include glycerin, trimethylolpropane, polyols such as pentaerythronate, amino alcohols such as jetanolamine, triethanolamine, and tripropaturamine; ethylenediamine, 1
, 6-hexanediamine, diethylenetriamine, toluylenediamine, etc., and a mixture thereof with ethylene oxide, propylene oxide, etc., and a molecular weight of 300 to 700° and a functional group number of 3 or more.

In the case of polyether polyol, if the molecular weight of the polyether polyol is less than 300, the reaction occurs too quickly, making it difficult to control the reaction with a catalyst, and the impact resistance of the cured product decreases.

On the other hand, if the molecular weight of the polyether polyol is larger than FOO, the cured product will not have the rigidity and heat resistance required as a structural material. Even if the molecular weight of the polyether polyol is in the range of 300 to 700, practical rigidity and heat resistance cannot be obtained when the polyether polyol has two functional groups.

The chain lengthening agent (FC) that can be used in the present invention is ethylene glycol, 1,3-methanediol, or a mixture thereof. In this case, other compounds such as 1
．． 4-butanediol, 1.6-hexanool, dipropylene glycol, diethylene glycol and the like are also commonly known as chain lengthening agents in polyurethane compositions.

1.4-butanediol, 1,6-hexanediol and the like are undesirable because their winter solids are solid at room temperature, and require a dissolution step when blended into polyether polyols, and also cause separation of the blended liquid during winter.

Also, chain detergents with relatively large molecular weights such as birene glycol, diethylene glycol, and 1.6 hexanediol. When used, the hard segment of urethane becomes stiff, and as a result, good rigidity and heat resistance cannot be obtained.

The equivalent ratio of isocyanate group (NCO)/hydroxyl group (O)l) in the present invention is from 0.9 to 1.2, preferably from 1.0 to 1.1'''C.

And the ratio of organic polyinocyanate and polyol (polyether polyol + chain length agent) is 130/100.
~180/1007! and the amount of organic polyisocyanate is less than this range.

Heat resistance tends to be poor, and on the other hand, if the amount of organic polyisocyanate exceeds this range, impact resistance tends to be poor.

The ratio of polyether polyol (Al and chain lengthening agent (C)) in the present invention is 100/4 to 100/1.
A range of 100 is preferred. Particularly preferably 10015~
It is in the range of 100/60.

The curing catalyst (d+) that can be used in the present invention is an imidazole compound represented by the general formula (1).
(1) Cnl(2+u (m''1-4.n=an integer of 1-4) A typical example is 1,2-dimethylimidazole.

Examples include 1-butyl-2methyl imiguzole.

Note that in the present invention, urethanization catalysts known in the art can also be used together. Typical examples are triethylamine,
Tripropylamine, tributylamine, N-methylmorpholif, N,N-dimethylcyclohexylamine, N
, N-dimethylbenzylamine, N, N, N:
N'-tetramethylhexamethylenediamine, triethylenediamine.

1,8 diazabicic O(5,4,0) undecene-7
Examples include tertiary amines such as tertiary amines, organic acid salts thereof, and organometallic compounds such as nutana octoate, dibutyltin dilaurate, and zinc naphthenate.

Long fiber mats that can be used in the present invention include:
Glass fiber, carbon f11. Examples include chopped strand mats, continuous strand mats, surfacing mats, cloths, and roving cloths made of aramid fibers. Two or more of these long fiber mats may be used in combination.8 In the present invention, the ratio of the polyurethane resin composition to the long fiber mat is preferably 90/10 to 50,150 by weight.

If the ratio of long fiber mat is too low.

If the rigidity is insufficient, and if the amount is too high, it becomes difficult to impregnate the long fiber mat with the polyurethane resin composition, which is not preferable.

In the present invention, various wire nets 1 and mesh-shaped molded products of synthetic resin can be used in combination with long fiber mats, if necessary. Also 9
The present invention uses a blowing agent as necessary.

Flame retardant 9 Colorants, various fillers, internal deafening agents, and other processing aids can be added.

〔Effect of the invention〕

The fiber-reinforced polyurethane resin composition of the present invention is quick-curing, and the cured product has excellent impact resistance and heat resistance.

Because of its rigidity, it is extremely useful as a structural member for, for example, bumper beams, floor panels, door inner panels, door liners, headliners, dash boards, pillar covers, and other general industrial parts in the automobile field.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.
The present invention is not limited to these.

The physical properties were measured using the following method.

Measurement item Measurement method Specific gravity JIS K
-7112 Bending elasticity $JIS K-7203 Bending strength JIS K-7203 Izotsu @Hayabusa notch JIS K-711
0pqR type in degree (18,5kgf%-load TOJIS
K-7207 Examples 1-3. Comparative Examples 1 to 2 Glasslon M8609 (Glass Continuous Matte, manufactured by Asahi Fiberglass, trade name) (il-
150 parts by weight of MR200 (polyphenylene polymethylene polyisocyanate NCO content 30.9% 2 trade name manufactured by Nippon Polyurethane Industries) and 150 parts by weight of ADEKA Polyether AM30 (glycerin-based polyether polyol hydroxyl value 540. 93.9 parts by weight (trade name, manufactured by Asahi Denka Kogyo), 6.1 parts by weight of ethylene glycol, and a curing catalyst shown in Table IK were stirred and mixed in a metal laboratory mixer, and the mold was immediately clamped after injection. After 2 minutes of clamping, the mold was removed and the tack on the surface of the molded plate was examined.

In each formulation, the amount of catalyst was adjusted so that the gel time was 20 to 30 seconds.

The results are shown in Table IK.

Table 1 Example 1 Example 2 Example 3 Comparative example 1 Comparative example 21
．． 2 dimethylimitanol 0.3
0.2 0.2S --DABCO
33LV1) -0,1-0,25-Towaq-Nomezapui7rio-Jhin＾riichimin
- -0,1-0,5 tack of formed plate
No jIls Yes
Notes to Table 1 1) Triethylene diamide/dipropylene glycol solution Manufactured by Sankyo Air Products Product name and amount of catalyst used are percentages by weight based on the polyurethane resin composition.

Examples 4-6. Comparative Examples 3 to 4 Glassron M8609 was placed in the same 50°C mold as in Example 1, and the components A and B shown in Table 2 were injected into the mold using a low-pressure two-component mixing injection machine (MU203H manufactured by Polyurethane Engineering). After tightening 3'F, the mold was demolded twice to obtain a molded plate.

physical properties It is shown in Table 2.

Notes for Table 2 below: 1) Carbodiimide group-containing liquid diphenylmethane diisocyanate NCO content 288%, manufactured by Nippon Polyurethane Industries, Ltd. Product name 2) Polyoxypropylene triol, hydroxyl value 402, manufactured by Sanyo Chemical Industries, Ltd. Product name 3) Polyoxypropylene glycol, hydroxyl value 27071! 17II Kakogyo Product Name Example 7. Comparative Examples 6-7 Cavity size 3QOX250X2.5mm 50
Glasslon M8609 was placed in a mold at 30°C, and after closing the mold, the components A and B at 30°C shown in Table 3 were placed in a high-pressure reaction injection molding machine (RIM).
) (Polyurethane Engineering Mc102) was injected into the mold, and after 3 minutes the mold was removed to obtain a molded plate.

The formulation and physical properties are shown in Table 3.

Below margin Notes to Table 3 1) 1.8 Diaza-Biacro (5゜ Su/Made by Age cI Product name

Claims (1)

[Scope of Claims] A fiber-reinforced polyurethane resin composition comprising a long fiber mat and a polyurethane resin, in which the polyurethane resin is a, an organic polyisocyanate b, a polyether polyol c having a molecular weight of 300 to 700 and having 3 or more functional groups, and ethylene glycol. and/or 1,3-butanediol d, and an imidazole compound shown in general formula (1) as a curing catalyst ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ (1) (m = 1 to 4, n = 1 to 4 (an integer of ) A fiber characterized in that the ratio of a to b+c is 130/100 to 180/100 by weight, and the ratio of the polyurethane resin composition to the long fiber mat is 90/10 to 50/50 by weight. Reinforced polyurethane resin composition