JPS59461B2 - How to improve cement alkalinity resistance of glass fiber - Google Patents

Description

[Detailed description of the invention] Portland cements, lime milk Ca (OH) 2,
Attempts have been made to improve strength and durability by mixing glass fiber with mortar or plaster containing water glass, etc.
Although this method has been practiced by those skilled in the art both at home and abroad for quite some time, most of them have not been able to achieve any practical results.

The main reason for this is that Ca(OH)2, MS/(OH)2, and K are liberated during the hydration solidification reaction of these cements.
OH, NaOH, etc. soak the surface of glass fibers, reducing their tensile strength, and even after solidification, such as Portland cement, Ca(O
H) 2 etc. are contained in an aqueous solution state, and this Ca
This is because (OH)2 contacts the fibers and reduces their tensile strength.

In order to prevent the glass fibers from being immersed in the remaining Ca(OH)2, it would be good if the glass fibers could be coated with a cement-alkali-resistant material at low cost and easily.

Here, the present inventor came up with the idea of coating glass fiber with a cationic asphalt emulsion, and using this,
The results were very good, and it was confirmed that the cement alkali resistance of glass fibers was particularly improved.

In conventional asphalt emulsions, all of the asphalt particles contained therein are dispersed in water with a (-) charge, but the asphalt particles contained in cationic asphalt emulsions are dispersed by a special method 1. powerful(
It is given a + charge and dispersed in water.

The most important feature of cationic asphalt emulsions is that all asphalt particles are given a strong (g) charge.

Therefore, when glass fibers are immersed in a cationic asphalt emulsion, as shown in the figure, the (a) charges of the asphalt particles are easily attracted to each other around the entire circumference of the glass fibers (which have an electric charge of @), and when there is moisture, As long as the two are electrically bonded firmly.

That is, as can be seen from the drawings, the perforated glass fibers coated with the cationic asphalt emulsion have very low cement alkali resistance.

Examples will be described below.

Example 1 Ten alkali-containing glass fibers were taken and mixed with asphalt cationic emulsion C manufactured by Nichirei Kagaku Kogyo Co., Ltd.
The fibers were immersed in a 50% (volume) solution of ME-3 (trade name, the same hereinafter) at room temperature for 30 minutes, and the immersed fibers were further soaked in Portland cement supernatant liquid (PH 12-14) at a temperature of 9.
The cement alkaline resistance was tested by immersion treatment at 0 to 95° C. for 2.5 hours, and the results are shown in the following table.

As shown in the table above, the average strength of the untreated product is 49.92Icg.
/mL This treated with CME-3 is 62,5
0 kg/mat, and that which was further immersed in Portland cement supernatant liquid showed an improvement to 71.92 kg/mIL.

This indicates that the cement alkali resistance is rather improved.

Example 2 Take 20 alkali-containing glass fibers with a length of 100 cIrL and a fineness of 19 to 22μ, and divide them into two parts of 50 m each as follows: A (20 fibers)... Untreated B (20
Book piece......Those treated according to the present invention First, A
A strength test was conducted on each untreated portion, and then this was added to the Portland cement supernatant at 90-95°C for 2.5 minutes.
A strength test was performed on the time-treated samples, and the average value for each was recorded.

Next, from B, a strength test was carried out using the method of the present invention, which was immersed in a cationic asphalt emulsion (CPE-4, trade name) manufactured by Nichirei Kagaku Kogyo Co., Ltd. for 20 minutes at room temperature. Liquid PH12
The results of the strength test of the samples treated at 90 to 95° C. for 2.5 hours at ~14° C. are shown in the table below.

In addition, sodium palmitate (PN) CH3 (CH2) 14COONa or lauryltrimethylammonium chloride (WC) (CHa (CH2) 11 N (CHa )
s] A trace amount of Ct+, that is, sodium palmitate is 0.
1%, lauryltrimethylammonium chloride 0
．． Tests were conducted in the same manner with the addition of 1% and 0.5%.

This is because most of the Hymento is charged as (→) in water, but there is also a small amount of it as (), so we conducted a test with a small amount of these added, and conducted a strength test in the same way. Shown in the table below.

As shown in the table above, asphalt emulsion (CPE-4) has extremely low cement alkalinity resistance when untreated.
However, the alkaline resistance of the cement even after treatment showed a tendency to improve.

Furthermore, 0.1% sodium palmitate or 0.1% lauryltrimethylantimonia chloride, especially 0.
．． It is recognized that the tensile strength of the cement supernatant treated with 5% is improved.

Example 3 Same as Example 2, except that after treatment with asphalt emulsion, heat treatment was performed at 100° C. for 10 minutes.

This is to make the surface of the fiber smooth.

From the table above, it was found that there was no change even after drying at 100°C for 10 hours.

Example 4 In this example, emulsion A (trade name, PH7), which is a cationic asphalt emulsion manufactured by Nichirei Chemical Co., Ltd., was used, and everything else was the same as in Example 2.

As shown in the following table, there was no major difference from the previous example, and it was found that the cement had alkaline resistance.

[Brief explanation of drawings]

The drawing is an explanatory diagram of the principle mechanism of the method of the present invention.

Claims (1)

[Claims] 1. A method for improving cement alkalinity resistance of glass fibers, which comprises immersing glass fibers in a cationic asphalt emulsion to which a trace amount of lauryltrimethylammonium chloride or sodium palmitate is added to coat the surface of the glass fibers.