阅读说明：本技术 用于水下灌浆的环氧树脂组合物 (Epoxy resin composition for underwater grouting ) 是由 邵艳 叶炜洁 王兰伟 于 2018-03-21 设计创作，主要内容包括：本发明公开了可固化环氧树脂组合物,其含有至少一种具有每分子平均多于一个环氧基的环氧树脂、至少一种无机填料、至少一种水硬性粘结剂和至少一种聚羧酸化物醚,其中所述无机填料包含基于总可固化环氧树脂组合物计45至65重量％的量的二氧化硅,且所述聚羧酸化物醚的量为基于总可固化环氧树脂组合物计0.01至0.03重量％。本发明还公开了用于生产所述环氧树脂组合物的多组分体系、经固化环氧树脂和修补或增强桩或柱的方法。(Curable epoxy resin compositions are disclosed containing at least one epoxy resin having an average of more than one epoxy group per molecule, at least one inorganic filler, at least one hydraulic binder and at least one polycarboxylate ether, wherein the inorganic filler comprises silica in an amount of 45 to 65 wt. -%, based on the total curable epoxy resin composition, and the polycarboxylate ether is in an amount of 0.01 to 0.03 wt. -%, based on the total curable epoxy resin composition. Also disclosed are multi-component systems for producing the epoxy resin compositions, cured epoxy resins, and methods of repairing or reinforcing piles or columns.)

1. Curable epoxy resin composition for underwater grouting, containing at least one epoxy resin having on average more than one epoxy group per molecule, at least one inorganic filler, at least one hydraulic binder and at least one polycarboxylate ether,

wherein

The inorganic filler comprises silica in an amount of 45 to 65 wt% based on the total curable epoxy resin composition, and

the polycarboxylate ethers are present in an amount of 0.01 to 0.03 weight percent based on the total curable epoxy resin composition.

2. The curable epoxy resin composition according to claim 1, wherein the silica has a particle size <50 μm as determined by sieve analysis using a No. 325 mesh sieve in accordance with ASTM E11.

3. Curable epoxy resin composition according to claim 1 or 2, wherein the hydraulic binder is cement and is comprised in the composition in an amount of 5 to 10 wt% based on the total curable epoxy resin composition.

4. Curable epoxy resin composition according to at least one of the preceding claims, additionally containing at least one curing agent and/or at least one reactive diluent.

5. Curable epoxy resin composition according to at least one of the preceding claims, wherein the epoxy resin comprises at least one glycidyl ether and/or the curing agent contains at least one polyamine, preferably selected from the group consisting of aliphatic, cycloaliphatic or araliphatic primary diamines, triamines, tetramines, polyamines having more than four amine groups per molecule, polyamines containing secondary amine groups, amine/polyepoxide adducts, poly (ethyleneimine), polyamidoamines, mannich bases and amino-terminated butadiene/acrylonitrile copolymers.

6. Curable epoxy resin composition according to at least one of the preceding claims, wherein the polycarboxylate ether has side chains attached to a backbone via ester, amide and/or ether groups, wherein the backbone has at least one acrylic acid moiety or salt thereof and/or at least one methacrylic acid moiety or salt thereof.

7. Curable epoxy resin composition according to at least one of the preceding claims, wherein the polycarboxylate ether is a comb polymer comprising structural units (i) of formula II and structural units (II) of formula III,

Wherein

R¹Independently of one another represent-COOM, -SO₂–OM、-O–PO(OM)₂and/or-PO (OM)₂，

R²And R⁵Independently of one another, H, -CH₂COOM or alkyl having 1 to 5 carbon atoms,

R³and R⁶Independently of one another, H or an alkyl radical having 1 to 5 carbon atoms,

R⁴and R⁷Independently of one another, represents H, -COOM or an alkyl radical having 1 to 5 carbon atoms,

or wherein R is¹And R⁴Together form a-CO-O-CO-ring (anhydride),

m independently of one another represents H⁺Alkali metal ions, alkaline earth metal ions, ammonium cations, organic ammonium compounds, divalent or trivalent metal cations, or mixtures thereof;

m is 0, 1 or 2,

p is 0 or 1, and p is 0 or 1,

x independently of one another represents-O-, NH-or-NR⁸-，

R⁸Independently of one another, represent formula [ AO]_n-R^aThe group of (a) or (b),

wherein A ═ C₂-to C₄Alkylene radical, R^aRepresentative H, C₁-to C₂₀-alkyl, -cyclohexyl or-alkylaryl,

and n ═ 2 to 250, particularly 10 to 200.

8. The curable epoxy resin composition according to claim 7, wherein

R¹Represents a group of the formula-COOM,

R²、R⁴、R⁵、R³、R⁶and R⁷Represents a compound of formula (I) or (II),

m independently of one another represents H⁺Alkali metal ions or alkaline earth metal ions;

m is 0, p is 1, X represents-O-,

R⁸is represented by the formula- [ AO]_n-R^aThe group of (a) or (b),

wherein A ═ C₂Alkylene, especially C₂Alkylene radical, R^aRepresents CH₃And is and

n is 22 to 72.

9. Multicomponent system for producing a curable epoxy resin composition according to at least one of the preceding claims, comprising a component K1 comprising the at least one epoxy resin and a curing agent component K2 comprising at least one curing agent, wherein the inorganic filler, the hydraulic binder and the polycarboxylate ether are comprised in the component K1, the component K2 or an additional component K3.

10. The multicomponent system according to claim 9, wherein the multicomponent system is a two-component system comprising component K1 comprising the at least one epoxy resin and curing agent component K2 comprising at least one curing agent, wherein the inorganic filler, the hydraulic binder and the polycarboxylate ether are comprised in the component K1.

11. Two-component system according to claim 10, wherein component K1 comprises

-15 to 35 wt% of the epoxy resin based on the total component K1;

-0 to 5 wt% of an epoxy functional diluent based on the total component K1;

-0 to 0.1% by weight, based on the total component K1, of a defoamer;

-5 to 10% by weight of said hydraulic binder, based on the total component K1;

-50 to 70 wt% of the inorganic filler, based on the total component K1;

-0.015 to 0.025 wt% of the polycarboxylate ether, based on the total component K1;

and the component K2 comprises

20 to 60% by weight, based on the total component K2, of at least one polyamine;

-0 to 15 wt% of accelerator based on the total component K2;

0 to 50% by weight, based on the total component K2, of a solvent;

wherein all amounts of individual components in each of the components K1 and K2 are adjusted such that the sum of all individual amounts does not exceed 100% in the respective component K1 or K2.

12. Cured epoxy resin obtainable by curing an epoxy resin composition according to at least one of claims 1 to 8 or by mixing the components of a multi-component or two-component system according to at least one of claims 9 to 11 and curing the system.

13. A method of repairing or reinforcing a pile or column comprising the steps of:

a) optionally pre-treating the pile or post by cleaning, sand or wet blasting, priming and/or brushing;

b) installing a sleeve around the pile or post covering the damaged area of the pile or post surface such that the sleeve surrounds the pile or post leaving a gap between the surface of the pile or post and the inner surface of the sleeve;

c) sealing the sleeve against the pile or post, in particular at the lower opening;

d) introducing a curable epoxy resin composition according to at least one of claims 1 to 8 or an epoxy resin composition obtained by mixing a multi-component or two-component system according to at least one of claims 9 to 11 in a suitable ratio into the gap between the sleeve and the pile or post;

e) curing the epoxy resin composition.

14. A method according to claim 13, wherein the pile or column is at least partially submerged in water.

15. A method according to claim 12 or 13, wherein the piles or columns are made of concrete and/or steel.

Technical Field

The invention relates to a curable epoxy resin composition for underwater grouting, comprising at least one epoxy resin having on average more than one epoxy group per molecule, at least one inorganic filler, at least one hydraulic binder and at least one polycarboxylate ether.

The invention also relates to two-component systems for producing epoxy resin compositions, cured epoxy resin compositions and methods for their use.

Background

Epoxy resins are used in various applications, for example as adhesives, coatings, sealants or molding compositions for producing moldings. Of these, compositions comprising fillers and/or hydraulic binders are often used in grouting applications. Such filler-containing compositions exhibit good mechanical properties as well as chemical, environmental and mechanical resistance and have good adhesion properties on substrates such as natural stone, concrete and other building surfaces.

One particular field of application is the renovation or reinforcement of concrete foundations in water in buildings such as wharfs or bridges (platforms in which concrete columns, piles and other foundation elements are used to support alongside or on a body of water). Especially at seaside, where strong natural forces and high water movement are common and the brine itself has highly corrosive properties, these infrastructures are often subjected to severe mechanical and chemical degradation and at some point require repair work to maintain their ability to support the structure built above them. Without any repairs, these affected infrastructures show concrete damage and steel bar exposure, and they eventually collapse.

A compact and cost effective method of reinforcing an underwater pile or column involves installing a glass fibre sleeve around the damaged pile or column and introducing grouting material between the damaged pile or column and the inside of the glass fibre sleeve. After curing, the grout forms a firmly adhering intermediate layer between the pile or column and the sleeve and additionally fills cracks and holes and significantly strengthens and protects the overall structure from future wear. This method has been known since the 70 s of the twentieth century and is continually being optimized and further developed. For example, chinese utility model CN 205205695U or chinese patent application CN 105862574A teach this approach in a recent scenario.

However, this method requires a highly compliant grout that cures properly also under water, as wear of the concrete pile or column can also occur in partially or fully submerged sections. Many epoxy-based grouting materials do not meet the desired properties and do not cure and/or adhere properly to substrates when contacted with water, particularly seawater.

Therefore, special epoxy-based grouting materials have been developed, which are generally suitable for this task. It has been found that BaSO is used₄As a filler in epoxy-based grouting materials, it brings good underwater curing behaviour, since it makes the composition heavy by density increase and generally provides good flowability and low oil absorption in the material, which is advantageous. However, BaSO is often observed₄The filled composition easily disperses or separates when poured into water and the filler is washed out over time, reducing the overall performance of the cured grout.

Other commonly used fillers excessively increase the viscosity of the composition, which places a heavy burden on the workability of the composition.

In general, a continuing problem in this field is balancing the flowability and dispersibility of such epoxy-based grouting compositions in water.

In general, it is desirable to provide epoxy-based curable grouting compositions that are inseparable underwater and cure rapidly, do not exhibit shrinkage, have low viscosity and good workability and generally excellent performance in terms of mechanical properties, chemical, mechanical and fatigue resistance, and adhesion particularly on wet or damp concrete.

Disclosure of Invention

Object of the Invention

The object of the present invention is to overcome the above problems.

In particular, the present invention is intended to provide curable epoxy resin compositions with good flowability, which exhibit excellent underwater handling and curing behavior as well as excellent mechanical properties and adhesion, in particular underwater. Further, it is an object of the present invention to provide a method for repairing or reinforcing piles or columns, in particular piles or columns which are at least partially submerged in water, using the curable epoxy resin composition of the present invention.

Detailed Description

Exemplary embodiments

The following examples illustrate some embodiments of the invention. The term "standard climate" refers to a temperature of 23 ℃ and a relative humidity of 50% (r.h.).

Test method

The fluidity of the epoxy composition was determined according to the Chinese Standard JC/T986-. All individual components of the test compositions were preconditioned for at least 8 hours in a standard climate (23 ℃, 50% r.h.). All components were mixed together with a mixing spindle attached to a slow electric drill (max 400rpm) for at least 3 minutes until the consistency of the material was smooth and of uniform colour. Bottomless cones (height: 60 mm. + -. 0,5 mm; internal diameter at the top: 70 mm. + -. 0,5 mm; internal diameter at the bottom: 100 mm. + -. 0,5mm) were placed vertically on a glass plate and filled to the edge with the mixed composition. Using a stopwatch, the time was initially recorded and the test mold was lifted 5-10cm and held in place for at least 15-20 seconds to allow the composition to completely drip off. The composition began to spread in all directions on the glass plate. After 30 minutes, the diameter of the flow spread was measured in two directions at right angles to each other. The results reported (flowability) are the average of those diameters in mm.

Compressive strength was measured according to EN 196 standard using cured (1d or 7d standard weather ("air") and 1d or 7d underwater ("underwater"), 23 ℃) epoxy-based composition prismatic test specimens (40X 160mm) and a load increase rate of 2400 + -200N/s.

Flexural strength was measured according to EN 196 standard using cured (1d or 7d standard weather ("air") and 1d or 7d underwater ("underwater"), 23 ℃) epoxy-based composition prismatic test specimens (40X 160mm) and a load rate of 50. + -.10N/s.

The density (specific gravity) is determined according to EN ISO 2811-1:2001 standard, using a preconditioned 100mL metal pycnometer at a temperature of 20 ℃.

Adhesion to concrete (bond strength by pull off adhesion test) was determined according to the EN 1542 standard by direct pull using a steel sliding stand (dolly) bonded to the surface of the cured composition. The dimensions of the concrete/substrate sample were 300X 100 mm. The surface was sandblasted according to EN 1766. The samples labeled "cure in air" were cured using a dry concrete base in a standard climate for 7 days. The samples labeled "cured underwater" were cured underwater (23 ℃) for 7 days using a wet concrete substrate that had been submerged in water for at least 24 hours prior to application of the epoxy-based composition. For the pull-off experiments, the load was continuously and uniformly increased at a rate of 0.05. + -. MPa/s for each test assembly.

The uncured or cured samples of the epoxy-based compositions were evaluated for underwater behavior by optical inspection. In each experiment, 150 ml of clear water was filled into 200 ml clear plastic cups. Thereafter, 100 and 150 grams of the freshly mixed sample composition was poured into the water in the cup. Typically, the composition sinks to a bottom and remains there. The floating particles of the aqueous phase were visually inspected and the appearance of the epoxy-based grout layer formed was inspected. A "good" result requires that the water is clear and free of floating particles, coloration or turbidity (dispersing effect). At the same time, a "good" result requires that the epoxy grout layer be uniform, dense and crack-free. Any deviation from this ideal behavior is noted in the evaluation results.