JPS6125669B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to cement formulations. More specifically, the present invention relates to a fibrous cement composition comprising polyethylene or polypropylene mixed with an epoxy resin. It has been known to mix synthetic resin fibers, split fibers, metal fibers, glass fibers, etc. with the aim of improving the bending strength, crack resistance, etc. of cement products. However, among these fibers, for example, synthetic resin fibers do not mix well with cement, and the fibers are entangled with each other, making it difficult to disperse them in cement, which often results in uneven strength in cement products. In addition, since the shape is simple, it easily comes off when bending stress is applied, and the reinforcing effect is not sufficient. In addition, synthetic resin split fibers have a complicated shape,
Although it is thought that the physical bond with the cement is greater, in reality, it is kneaded into the cement in a bent state, so the retentivity effect is not so great. Furthermore, since the split fibers themselves are bulky, they have the disadvantage of being difficult to disperse uniformly. Metal fibers and glass fibers have a relatively good affinity with cement and can provide a considerable reinforcing effect, but they are expensive and the fibers are highly entangled, so special defibration machines or mixers, such as fiber The disadvantage was that a dispenser, omni mixer, auger mixer, etc. were required. The present applicant has already filed Japanese Patent Application No. 55-5235 regarding a cement compound that is easily dispersed in cement and has an excellent reinforcing effect. The present invention was arrived at as a result of further study on materials for cement compounds, and relates to a fibrous cement compound made by blending polyethylene or polypropylene with an epoxy resin. The polyethylene or polypropylene that can be used in the present invention is a homopolymer of ethylene or propylene, or a product obtained by random copolymerization, block copolymerization, or random copolymerization of ethylene or propylene as a main component and other polymerizable monomers. Such polyethylene or polypropylene is suitable for the present invention because it has excellent rigidity and good moldability. The epoxy resin as used in the present invention is generally referred to as an epoxy resin having one or more epoxy groups in one molecule chain, and includes, for example, epihalohydrin such as epichlorohydrin or dihalohydrin such as glycerine dichlorohydrin and 2,2-
Bis(4-hydroxyphenyl)propane (commonly known as bisphenol-A), 2,4-hydroxydiphenylmethane, bis(2-hydroxyphenyl)
Methane, bis(4-hydroxyphenyl)methane (commonly known as bisphenol F), 1,1-bis(4-hydroxyphenyl)ethane, bis(4-hydroxy-2,6-dimethyl-3-methoxyphenyl)
Polyhydric phenols such as methane, resorcinol, hydroquinone, and catechol, and polyhydric phenols such as the above-mentioned nuclear substitutes and halides, as well as ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,4
-butanediol, 1,3-butanediol,
1,5-pentanediol, 1,3-pentanediol, 1,6-hexanediol, 1,5-hexanediol, neopentyl glycol, trimethylolethane, trimethylolpropane, glycerin, 2-methyl glycerin, bentaerythritol alkanes ( _C2 - _C30 ) poly(n=
2-6) Alcohol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, poly(n=1-40) oxyalkylene glycol, polybutadiene glycol, hydroxyl terminal Ptadiene-acrylic nitrile copolymer, hydrogenated bisphenol-A, glycol added with ethylene oxide or propylene oxide of bisphenol-A, polyhydric alcohol added with ethylene oxide or propylene oxide of phenol/novolac resin, tallow oil, whale oil, fish oil; rice bran Polyglycidyl ethers obtained by reaction with alcohols obtained from animal and vegetable oils such as oil, castor oil, etc., their halides, polyhydric alcohols such as nuclear water additives, or epihalohydrin or dihalohydrin and alcohols. acid,
fumaric acid, maleic acid, succinic acid, glutaric acid,
Adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, methyltetrahydrophthalic acid, methylhexahydrophthalic acid, endomethylene polyglycidyl esters obtained by reaction with polycarboxylic acids such as tetrahydrophthalic acid, methylendomethylenetetrahydrophthalic acid or their halides;
Furthermore, epoxy resins having an internal epoxy group such as 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate and ethylene glycol bis(3,4-epoxydihydrodicyclopentadienyl) ether, 3,
Examples include epoxy resins containing both terminal epoxy groups and internal epoxy groups, such as 4-epoxycyclohexylmethylglycidether. Among these epoxy resins, polyglycidyl ethers of polyvalent phenols are preferred, and diglycidyl ethers of bisphenol A, bisphenol F, and 1,1-bis(4-hydroxyphenyl)ethane have a viscosity at 25°C. 100 or more
Most preferred is an epoxy resin of 15,000 cps and an epoxy equivalent weight of 300 to 5,000. To blend epoxy resin with polyethylene or polypropylene, various conventionally known mixers,
For example, a Henschel mixer, a Banbury mixer roll, an extruder, etc. can be used, and a master batch may be prepared in advance and blended. The amount of epoxy resin blended into polyethylene or polypropylene is 0.1 to 50% by weight, especially 3
30% by weight is preferred. If it is less than 0.1% by weight, the improvement effect is small, and if it increases to 50% by weight, the effect may not change much, or the improvement effect may even decrease. In addition to the curing agent for the thermosetting resin, the cement composition of the present invention may also include various compounding agents such as heat stabilizers, weather stabilizers, lubricants, slip agents, dyes, pigments, and flame retardants. , antistatic agents, organic and inorganic fillers, blowing agents, crosslinking agents, hydrolyzable groups such as vinyltrimethoxysilane, organic silane compounds containing groups with unsaturated bonds, silane coupling agents, etc. Ru. Cement formulations are formed into various shapes.
For example, it is formed into a sheet or film by extrusion molding such as the inflation method or T-die method, and then cut into sections in the longitudinal direction, and then each is stretched to form a tape. After stretching, it can be divided and cut in the stretching direction to form a tape shape to obtain a blend. Furthermore, a fibrous cement compound can be obtained by stretching a film or sheet and then splitting the fibers. Among them, a stretched string-like body is preferable, and in addition to the method of forming an embossed stretched tape-like body as proposed in the above-mentioned Japanese Patent Application No. 53-5235,
A method in which one or more wire rods such as monofilament are run through a binding machine to form knots to create unevenness, and a thin rod with small unevenness is extruded using a die such as a caterpillar die.
There are a method of drawing, a method of twisting two or more wire rods such as monofilament together using a twisting machine, and the like. Another embodiment is a method in which melt extrusion is performed under molding conditions that cause irregularities on the surface of the molded product immediately after melt extrusion, and stretching treatment is performed, for example, the surface of the molded product has pine skin, rough texture, or melt fracture. A stretching treatment is carried out after melt spinning under the conditions that occur. For this purpose, polypropylene whose MI (melt index, value measured based on ASTM-D-1238-65T) (230°C) is 0.1 to 20 or polyethylene whose MI (190°C) is 0.01 to 40, Among them, polyethylene with an MI of 0.01 to 10, especially polyethylene with an MI of less than 0.01.
It is preferable to use polyethylene with an MI adjusted to 0.01 to 10 by blending polyethylene exceeding 10%. It is also desirable that these blends be stretched 3 to 20 times, particularly 6 to 12 times. The diameter is about 50 to 50,000 denier, especially about
Preferably it is 3000 to 12000 denier. The manner of blending the compound into cement is as follows:
The following are exemplified. In other words, it can be processed into various forms and mixed into cement, such as cutting it into arbitrary lengths, tying it into one or several loops, or twisting two or more strands together into a fiber. Ru. Among them, the length is about 5 to 100 mm,
In particular, it is preferable to cut it into pieces of about 30 to 80 mm before use. Cement with which the composition of the present invention can be mixed include hydraulic cements such as portland cement, white portland cement, alumina cement, silica cement, magnesia cement, pozzolan cement, air hard cements such as plaster and coal, and acid-resistant cements. In addition to special cements such as, various cement mortars, and inorganic materials such as calcium carbonate, magnesium hydroxide, and titanium white,
One or more types of earth and sand such as wall soil can be used. These cements may be blended with paraffin, wax, thermosetting water-soluble resins such as resol-type phenolic resins, various polymer emulsions, hardening accelerators, hardening retarders, etc., as necessary. The formulations of the present invention are incorporated into materials consisting of various inorganic materials or mixtures of these and other materials as described above. The amount of compounding compound added to cement is usually in the range of 1 to 30% by weight, preferably 3 to 15% by weight.If the amount is less than this range, the reinforcing effect will be poor, while if it exceeds the above range, the amount of compounding will be The proportion of substances becomes too large, making uniform dispersion difficult. The method of blending the compound of the present invention into cement is to mix cement with raw materials such as sand and silica if necessary, then add and mix the compound of the present invention, and further add water and knead. , a method of curing this, or a method of adding and mixing the compound of the present invention into a raw material mixture mixed with water. The cement formulation according to the invention has an excellent reinforcing effect. Although the cause of this is not clear, it is thought that the activation of the surface of the cement composition of the present invention and improved affinity with cement may also contribute. The cement molded body containing the compound of the present invention is
It has improved impact resistance and is highly effective in preventing cracking and edge chipping. Therefore, various cement molded bodies, such as underwater structures such as tetrapods,
Used for runways, bridges, tunnels, etc., as well as mortar, walls, precast boards, speaker boxes, seawall blocks, fence blocks, tiles, sleepers, hump pipes, paving blocks, tiles, planters,
It will be mixed into park benches, etc. Examples are shown below. Examples 1 to 4 and Comparative Examples 1 and 2 [Preparation of blends] The compositions having the compositions shown in Table 1 were fed to an extruder, and the resin temperature was set at 250°C (Examples 1 and 2 and Comparative Example 1) or 280°C. ℃ (Examples 3 and 4 and Comparative Example 2) from a 2.5 mmφ x 6-hole nozzle at a pressure of 150 to 220
After spinning at Kg/cm ² , it was stretched and further cut into lengths of 40 mm to obtain a blend. The formulations of Examples 1 and 2 and Comparative Example 1 had smooth surfaces, but the formulations of Examples 3 and 4 and Comparative Example 2 had similar surface irregularities. Table 2 shows the results of measurements of these formulations using the following method. [Preparation of specimen] This was carried out in accordance with JIS R 5201, that is, 100 parts by weight of Portland cement and 200 parts by weight of Toyoura standard sand were thoroughly mixed, and the mixture obtained by the above method was cut into lengths of 40 mm. After that, add 10 parts by weight of each, knead for a while, add about 65 parts by weight of water, knead until the whole is homogeneous, and then mix it into a 40mm×
It was packed into a 40 mm x 160 mm mold and cured for 7 days, 24 hours in the air and 6 days in water. [Measurement of bending strength] The specimen obtained by the above method was tested using an Instron testing machine, with a span of 100 mm and a bending speed of 1 mm/min.
Measurement was performed with a bending jig tip curvature of 5R.

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Claims (1)

[Scope of Claims] 1. A fibrous cement compound characterized by blending polyethylene or polypropylene with an epoxy resin. 2. The fibrous cement composition according to claim 1, which is polyethylene having an MI (190°C) of 0.01 to 40 or polypropylene having an MI (230°C) of 0.1 to 20. 3. The fibrous cement composition according to claim 1 or 2, which is an epoxy resin having a viscosity (25° C.) of 100 to 15,000 cps and an epoxy equivalent of 300 to 5,000. 4. A fibrous cement compound according to any one of claims 1 to 3, which contains 0.1 to 50% by weight of an epoxy resin. 5. The fibrous cement composition according to any one of claims 1 to 4, which has been stretched 3 to 20 times.