KR20130063062A - Polyurethane resin composition - Google Patents

Abstract

PURPOSE: A polyurethane resin composition is provided to have excellent workability, to facilitate impregnation into a tube by low viscosity thereof, and not to contain volatile organic solvent. CONSTITUTION: A polyurethane resin composition comprises polyester polyol with a molecular weight of 400-1000, and polyether polyol. The polyurethane resin composition consists of a base material with 10-25% of NCO, through a reaction of the polyester polyol, the polyether polyol, a chain extender, and isocyanate; glycol with a 2-4 chain-terminal hydroxyl functional group; and an aliphatic group modified-amine or an organic metallic reaction accelerator. The isocyanate is diisocyanates or polyfunctional isocyanates.

Description

Polyurethane resin composition for unexcavated water and sewage pipe regeneration and repair method {POLYURETHANE RESIN COMPOSITION}

The present invention relates to a polyurethane resin composition applied to a non-excavated water and sewage pipe regeneration and repair method, and more particularly, because the polyurethane resin composition has a low viscosity, it is easy to impregnate inside the tube and has excellent workability as well as volatility. volatile organic compound can be also cured to supply the hot air to a minimum by the boiler in the curing process does not contain an organic solvent (volatile organic compounds: VOCs) and carbon dioxide (CO ₂₎ ratio which can minimize the discharge digging a sewer play and It relates to a polyurethane resin composition for a repair method.

As is well known, various water supply and sewage pipes buried underground cause aging over time, causing corrosion in the water supply pipe. As a result, a large amount of water leaks into the water supply pipe, and drinking water is contaminated due to inflow of green water, and cracks occur in the fire water pipe, causing sewage to flow out to contaminate soil and groundwater.

As described above, in repairing buried pipelines damaged by aging of water and sewage pipes, it is common to apply non-excavated water and sewage pipe repair and regeneration methods to repair the entire buried pipeline. The non-excavated pipeline repair and regeneration method is a method of forming a new composite pipe in the water and sewage pipe by inserting a reinforcement tube into a damaged old buried pipeline without digging the ground. There are many advantages in this process.

In general, the reinforcing tube used for the repair and reconstruction of the non-excavated pipe line is formed of a waterproof film layer on the outer surface and an adhesive resin impregnation layer on the inner surface, and the reinforcing tube is attached to the inner portion of the buried tube. It is inverted inside so that the adhesive impregnated layer on the inner surface is inverted to the surface and adhered to the inner wall of the buried pipe, thereby adhering the reinforcing tube to the inside of the buried pipe.

On the other hand, conventional impregnation resins widely applied as adhesives for reinforcement and regeneration as described above include unsaturated polyester resins and epoxy resins. The unsaturated polyester resin includes maleic acid, allyl alcohol, and methyl alcohol produced by a hybrid polymerization reaction with a monomer having a condensate of an unsaturated polyhydric acid such as maleic acid and fumaric acid with a dihydric alcohol such as ethylene glycol or diethylene glycol. There is a dimalyl phthalate system mainly based on polybasic acid esters of unsaturated monohydric alcohols.

Unsaturated polyesters have good adhesion to inorganic and metals, and have excellent water resistance and electrical insulation, but for curing, carbon dioxide (CO ₂ ) is emitted because it is a thermosetting type that cures by continuously supplying hot air in a tube for a certain time. Since it is an organic solvent type adhesive, volatile organic compounds (VOCs) are emitted and are widely used for sewage repair and regeneration.

In addition, the epoxy resins include bisphenol A type epoxy resins, reaction products of bisphenol-A and epichlorohydrin, phenol noblock resins prepared from alkylated phenols and formaldehyde, NBR modified epoxy resins, urethane modified epoxy resins, and polyglycides. Dyl ether epoxy resins are applied. These epoxy-based combinations have excellent mechanical strength, excellent heat and water resistance, and excellent chemical resistance, abrasion resistance, and adhesion to inorganic materials such as metal and cement, and thus are widely used for repairing and regenerating water pipes.

In particular, the impregnating resin used as an adhesive for reinforcing and regenerating tubes as in the prior art, in particular, unsaturated polyester resin and epoxy resin is different in tube diameter for curing, but hot water or steam from 10 hours to 10 minutes There was a disadvantage of having to supply for time. In order to supply steam and hot water for such a long time, a lot of energy costs are required to operate the boiler, and environmentally-friendly carbon dioxide emissions are increased, and long-term operation of the equipment causes inconvenience to the surroundings.

The present invention is to solve the conventional problems as described above, the polyurethane resin composition for non-excavated water and sewage pipe regeneration and repair method that can be used for water and sewage repair and regeneration as it is excellent in workability and adhesion and improved environmental friendliness The purpose is to provide.

In addition, another object of the present invention is to provide a polyurethane resin composition for non-excavated water and sewage pipe regeneration and repair method that can be cured by supplying steam up to 2 hours in addition to shortening the working time and cost reduction and carbon dioxide emission reduction. have.

The present invention relates to polyester polyols, polyether polyols, polyesters and polyethers having from 50 to 80% by weight of free NCO 10 to 25% by weight, and from 2 to 4 chain-end hydroxyl functional groups through the reaction of chain extenders with isocyanates. 20 to 50% by weight of a polyol and tertiary amine-based and organometallic reaction accelerators.

The present invention can be cured while significantly reducing the amount of steam hot water required for curing within a maximum of 2 hours, thereby reducing carbon dioxide generation from at least 1/2 to at most 1/5 as compared to conventional unsaturated polyester resins or epoxy resins. Not cost effective. Due to such characteristics, it is possible to minimize the equipment in the field, and also has an advantage of improving the operating efficiency of the equipment due to the shortening of the curing time.

Looking at the present invention in more detail as described above, the present invention is to implement a polyurethane resin composition for non-excavated water and sewage pipe repair and regeneration method improved workability and environmental friendliness.

The basic reaction mechanism of polyurethane is shown in Scheme 1 below.

[Reaction Scheme 1]

Polyester polyols that can be used in the present invention for the subject are condensates and hybrids of polybasic acids such as 1,4 butane carboxylic acid and benzene-M-carboxylic acid with dihydric alcohols such as ethylene glycol and diethylene glycol. There is a condensation polymer made by polymerization.

The polyether polyol may be a propylene oxide glycol and ethylene oxide glycol having 2 to 4 propylene oxide glycols having a chain-end hydroxyl function having a molecular weight of 400 to 2,000 g / mol.

Typical examples of the chain extender include ethylene glycol, 1,3 to 1,2-propylene glycol, 1,4 to 1,3 to 2,3 butylene glycol, 1,6 hexane glycol, neopentyl glycol, 1,4 Bis-hydromethylmethyl-cyclohexane. Short-chain diol compounds such as 2-methyl 1,3-propanediol, diethylene glycol and the like, and polyfunctional glycols such as trimethol propane are also possible.

Examples of the isocyanate include 1,4-tetramethylene diisocyanate, 1,6 hexamethylene diisocyanate, 1,12-dodecamethylene diisocyanate, cyclohexane-1,3- to 1,4-diisocyanate, 1-isocyanate-3 isocyanate Methyl-3,5,5-tremethylcyclohexane (isophorone diisocyanate), bis- (4-isocyanate cyclohexyl) methane (hydrogenated MDI), 2- to 4-isocyanate cyclohexyl-2-isocyanatecyclohexylmethane, 1,3- to 1,4-terramethylxylenediisocyanethi, 2,4- to 2,6-diisocyanate toluene, 2,2-2,4- to 4,4-diisocyanate diphenylmethane Diisocyanates, such as (MDI), 1, 5- naphthalene diisocyanate, xylene diisocyanate, diphenyl-4, and 4-diisocyanate, and polyfunctional isocyanates, such as polymethylene polyphenyl polyisocyanate, are also applicable.

On the other hand, polyester polyols having 2 to 4 hydroxyl functional groups usable for the curing agent of the present invention are hybrid polymerizations of 1,4 butane carboxylic acid having a molecular weight of 400 to 1,000 g / mol with ethylene glycol, diethylene glycol, and trimetholpropane. Condensates and propylene oxide glycols with molecular weights of 400 to 1500 g / mol are possible.

On the other hand, as the catalyst used in the present invention, an aliphatic modified amine and an organometallic catalyst can be used.

Polyurethane resin composition for unexcavated water and sewage pipe regeneration and repair method of the present invention made of a composition as described above has the following characteristics.

First, it can be cured with a minimum of heat source such as steam or hot water, and it has excellent adhesion and adhesiveness with the inner surface of the old pipe after curing.

Second, each component of the resin is not prohibited or regulated due to its harmfulness, and no organic solvents are used, so no by-products or odors occur during curing.

Third, the cured product has good and strong mechanical strength, and has excellent chemical resistance and water resistance.

Fourth, if the storage stability is high and the curing agent is not mixed, it can be stored for a long time regardless of the climate temperature and is not affected by sunlight exposure.

Hereinafter, the present invention will be described in detail with reference to preferred embodiments of the present invention, but the present invention is not limited to the embodiments.

{Example 1}

15.1 wt% of polyester polyol (molecular weight 400,700), 60.2 wt% of polymethylene polyphenylpolyisocyanate, and 25.7 wt% of 4,4-diisocyanate diphenylmethane, 100 wt% of the subject matter made of free NCO 21.5%;

60 wt% of a polyether (molecular weight 400,700) curing agent;

An organometallic catalyst of 1% by weight was blended to prepare a curable polyurethane resin for non-excavation repair. At this time, when the organometallic catalyst is 1% by weight or more, the curing reaction is accelerated, and the reverse process is impossible later.

The prepared polyurethane resin was impregnated with a PE film coated nonwoven fabric at about 2.0 kg / m 2, stored at -1 ° C. for 24 hours, and then inverted for 30 minutes, and then cured at 90 ° C. for 1 hour. The boiler and air pressure were removed and cooled to room temperature.

{Example 2}

15.3% by weight of polyether polyol (molecular weight 400,700), 53.5% by weight of polymethylene polyphenylpolyisocyanate, 31.5% by weight of 4,4-diisocyanate diphenylmethane, 100% by weight of main body made of 23.1% of free NCO;

A curable polyurethane resin for non-excavation repair was prepared by blending a 60% by weight polyether (molecular weight 400,700) curing agent.

The prepared polyurethane resin was impregnated with a PE film coated nonwoven fabric at about 2.0 kg / m 2, stored at -1 ° C. for 24 hours, and then inverted for 30 minutes, and then cured at 90 ° C. for 1 hour. The boiler and air pressure were removed and cooled to room temperature.

On the other hand, Example 1 and Example 2 presented above are summarized in Table 1 by each process.

fair Temperature time Remarks combination At room temperature (25 ° C) 30 minutes Viscosity: 500 ± 100 CPS, Specific Gravity: 1.08 ± 0.1 Impregnation At room temperature (25 ° C) 1 hours Impregnation amount: 1.8kg / ㎡ Storage and transport -1 ℃ 24 hours Reverse preparation Room temperature 30 minutes reversal Room temperature 30 minutes Air pressure: 0.4-0.5kg / ㎡ Hardening Room temperature 1 hours Air pressure: 0.4-0.5kg / ㎡ Curing Room temperature 30 minutes Pneumatic: 0.0kg / ㎡

The physical properties of the spot hardening tube produced by the process as described above are shown in Table 2.

Evaluation item Example 1 Example 2 Reference value Test Methods The tensile strength 250 230 More than 210kg / ㎠ KS M 3006: 2003 Flexural strength 430 410 320kg / ㎠ or more KS M 3015: 2003 Flexural modulus 18,700 18,300 17,600kg / ㎠ or more KS M 3015: 2003 Peel strength 210 240 178.6kg / ㎠ or more KS M D903: 1998

At this time, the test analysis was performed by the Korea Institute of Construction and Living Environment.

On the other hand, the dissolution test results of the cured polyurethane resin presented in Example 2 are shown in Table 3.

Test Items unit result Reference value Test Methods Turbidity Degree 0.5 0.5 or less




KS D 8502-99 Chromaticity Degree One 1 or less Potassium Permanganate Consumption mg / ℃ 2 2 or less Reduction of Residual Chlorine mg / ℃ 0.2 0.7 smell - clear No abnormality flavor - clear No abnormality draft - Not detected Not detected Phenols - Not detected 0.005 or less Amines - Not detected Not detected Epichlorohydrin mg / ℃ Not detected Not detected Toluene diisocyanate mg / ℃ Not detected Not detected

The mechanical properties of the cured polyurethane resin product shown in Example 2 are shown in Table 4.

Test Items unit result Reference value Test Methods The tensile strength kgf / ㎠ (MPD) 230 Satisfaction of constructor requirements

KS M 3015-2003 Flexural strength kgf / ㎠ (MPD) 410 Satisfaction of constructor requirements Compressive strength kgf / ㎠ (MPD) Satisfaction of constructor requirements Impact strength kgf / ㎠ (MPD) Satisfaction of constructor requirements Tensile Shear Adhesion Strength kgf / ㎠ (MPD) Satisfaction of constructor requirements Specific gravity (topic) - 1.1 KS M 3734-01 Specific gravity (hardener) - 1.08 KS M 5000-00

As shown in Table 1 to Table 4, the polyurethane resin composition according to the present invention is not only excellent in terms of workability and environmental friendliness, but also excellent in mechanical, physical, and chemical properties, suitable for repair and regeneration of water and sewage pipes. It can be seen that the substance.

Claims (4)

Polyurethane resin composition for unexcavated water and sewage pipe regeneration and repair method, comprising a polyester polyol having a molecular weight of 400 to 1000 and a polyether polyol.
The method of claim 1,
Subjecting the polyester polyol to a polyether polyol and a chain extender with an isocyanate to free NCO 10-25%;
Glycols having 2 to 4 chain-end hydroxyl functional groups;
Polyurethane resin composition for non-excavation water and sewage pipe regeneration and repair method comprising an aliphatic modified amine or organometallic reaction accelerator.
The method of claim 2,
The isocyanate is a polyurethane resin composition for non-excavation water and sewage pipe regeneration and repair method, characterized in that the isocyanates or polyfunctional isocyanates.
The method of claim 3,
The disisocyanates include 1,4-tetramethylene diisocyanate, 1,6 hexamethylene diisocyanate, 1,12-dodecamethylene diisocyanate, cyclohexane-1,3- to 1,4-diisocyanate, 1- Isocyanate-3 isocyanate methyl-3,5,5-tremethylcyclohexane (isophorone diisocyanate), bis- (4-isocyanate cyclohexyl) methane (hydrogenated MDI), 2- to 4-isocyanate cyclohexyl-2-isocyanate Cyclohexylmethane, 1,3- to 1,4-terramethylxylenediisocyanaeti, 2,4- to 2,6-diisocyanate toluene, 2,2-2,4- to 4,4-di Diocyanates such as isocyanate diphenylmethane (MDI), 1,5-naphthalene diisocyanate, xylene diisocyanate, diphenyl-4, 4-diisocyanate and polyfunctional isocyanates such as polymethylene polyphenylpolyisocyanate which Trenchless the sewer maintenance and reproduction method The polyurethane resin composition characterized in that (b)