CN105158109A - Method for detecting insoluble matter content of resin in liner layer of bamboo composite pressure pipe - Google Patents

Abstract

The invention discloses a method for detecting the resin insoluble content in the inner lining layer of a bamboo composite pressure pipe, which comprises the following steps: a detection step of a sample of the inner lining layer of a bamboo composite pressure pipe, a detection step of blank filter paper, and a blank non-woven fabric and the detection steps of the blank grid cloth, and the steps of calculating the insoluble content of the resin. Because there are differences in the structure and composition of the inner lining of different types of bamboo composite pressure pipes, other components except the resin in the inner lining will affect the accuracy of the detection of resin insoluble content. The impact of other components (such as non-woven fabrics and grid cloth) on the parameters of the insoluble content of the resin in the resin is taken into consideration, and the detection operation is simplified as much as possible under the premise of ensuring the accuracy of the detection results, which is convenient for practical use. use.

Description

A method for detecting the content of resin insoluble matter in the lining layer of bamboo composite pressure pipe

technical field

The invention belongs to the technical field of bamboo composite pressure pipes, and more specifically relates to a method for detecting the content of resin insolubles in the inner lining layer of bamboo composite pressure pipes.

Background technique

Bamboo material is a renewable green environmental protection material. In recent years, with the increasing maturity of bamboo composite pressure pipe related technologies (for example, Chinese patent documents CN101571213A, CN202327397U), bamboo composite pipe, as a pipeline that can withstand a certain pressure, is used in water supply and drainage. It can generally replace traditional pipes such as PVC pipes, polyethylene pipes, glass steel pipes, cement pipes, spiral welded pipes, and ductile iron pipes in engineering, farmland irrigation, and petrochemical anticorrosion, and has a good application prospect.

Bamboo composite pressure pipe, along the pipe diameter direction, includes an inner liner, a reinforcement layer and an outer protective layer from the inside to the outside, wherein the inner liner is usually made of resin, non-woven fabric and grid cloth on a straight pipe mold Form an anti-seepage and smooth inner lining; on the other hand, combined with the specific application conditions of the bamboo composite pressure pipe (such as the use environment, transmission medium, etc.), the structure and composition of the inner lining can also be modified In order to strengthen its performance, for example, acid and alkali resistant resin is selected to realize the transmission of highly corrosive media.

The quality of the inner lining layer affects the performance of the bamboo composite pressure pipe (such as short-term failure hydraulic pressure, long-term hydrostatic pressure, frost heaving adaptability, etc.), and the resin insoluble content is a measure of the quality of the inner lining layer. Important indicators. Resin insoluble content is also called degree of curing, and its detection principle is to extract soluble components in the resin with acetone close to the boiling point temperature, thereby obtaining the insoluble content in the resin; related prior art is also to the test of resin insoluble content For example, GB/T2576 was issued to standardize the test method for the insoluble content of fiber-reinforced plastic resin.

Although the existing technology has carried out relevant national regulations on the detection method of the resin insoluble content, when using the existing detection method to detect the resin insoluble content of the bamboo composite pressure pipe inner liner, the data obtained are often It cannot accurately and directly reflect the performance of the lining layer, and the test results have little reference value. In addition, because the components of the inner lining of bamboo composite pressure pipes may need to be adjusted according to the application conditions of bamboo composite pressure pipes, the results obtained by the existing detection methods for the insoluble content of resins are highly volatile. The physical meaning represented by the insoluble content is quite different, which brings great difficulties to the actual detection.

Contents of the invention

For the above defects or improvement needs of the prior art, the object of the present invention is to provide a method for detecting the resin insoluble content in the bamboo composite pressure pipe inner liner, wherein through its key process steps such as blank comparison test etc. Improvement, compared with the existing technology, it can effectively solve the problem that the resin insoluble content cannot accurately and directly reflect the performance of the inner lining layer, and the results obtained by this detection method for different inner lining layer components are fixed and reliable, and greatly simplified the actual detection operation.

In order to achieve the above object, according to the present invention, a method for detecting the content of resin insolubles in the inner liner of bamboo composite pressure pipe is provided, it is characterized in that, comprises the detection step of sample, comparative detection step and calculation resin insoluble sub-content step,

Wherein, the detection step of described sample comprises:

Strip off the inner liner on a part of the bamboo composite pressure pipe as a sample, the inner liner of the bamboo composite pressure pipe has n ₁ layer of non-woven fabric and n ₂ layers of grid cloth; the sample is dried , weigh the mass of the sample after cooling and record it as m ₆ ; then take the filter paper, weigh the mass of the filter paper and record it as m, then wrap the sample with the filter paper, and then place the Put the sample filter paper into the extraction device, add acetone to extract; after the extraction is complete, take it out together, drain it, dry it and dry it to a constant weight, and then cool it to get the extracted filter paper with the sample, which is called Measure the total mass of the filter paper containing the sample after the extraction, and record this mass as m ₄ ;

The comparative detection step includes a blank filter paper detection step, and a blank non-woven fabric and a blank grid cloth detection step,

Wherein, the blank filter paper detection step comprises:

Take the blank filter paper separately, the blank filter paper is the same type as the filter paper in the detection step of the sample, dry the blank filter paper, weigh its mass after cooling, record the mass as m ₇ , and then use the blank filter paper Put it into the extraction device, add acetone to extract; after the extraction is completed, take out the blank filter paper, drain and dry to constant weight, then cool to obtain the extracted blank filter paper, weigh the weight of the extracted blank filter paper mass, and record this mass as m ₈ ;

The detection steps of described blank non-woven fabric and blank mesh cloth include:

Separately take n ₁ layers of blank non-woven fabric and n ₂ layers of blank grid cloth, the type and number of layers of the blank non-woven fabric and the blank grid cloth are the same as those of the bamboo composite pressure tube in the detection step of the sample The type and the number of layers of the non-woven fabric and the grid cloth in the inner lining are the same; the n ₁ layers of blank non-woven fabric and the n ₂ layers of blank grid cloth are dried and dried, weighed after cooling, and weighed. Record this quality as m ₁ ; the n ₁ layers of blank non-woven fabric and n ₂ layers of blank grid cloth are wrapped with filter paper to form a filter paper equipped with blank non-woven fabric and blank grid cloth, and the blank grid cloth is equipped with Put the filter paper of non-woven fabric and blank grid cloth into the extraction device, add acetone for extraction; after the extraction is completed, take them out together, drain and dry to constant weight, and then cool to obtain the extracted Blank non-woven fabric and blank grid cloth filter paper, take out the extracted blank non-woven fabric and blank grid cloth, and weigh the quality of the extracted blank non-woven fabric and blank grid cloth, record the Mass is m ₂ ;

The step of calculating resin insoluble content comprises:

According to m ₆ , m , m ₄ in the detection step of the sample and m ₇ , m ₈ , m ₁ , m ₂ in the comparative detection step, it can be concluded that the resin in the inner lining layer of the bamboo composite pressure pipe is insoluble content.

As a further preference of the present invention, there are multiple samples in the detection step of the sample, and they are a plurality of samples with the same area stripped from different parts of the bamboo composite pressure pipe, which are respectively under the same conditions. Carry out experiments to obtain multiple sets of m ₆ , m and m ₄ data; in the blank filter paper detection step, there are multiple blank filter papers with the same area, and the tests are carried out under the same conditions respectively to obtain multiple sets of m ₇ and m ₈ Data; the blank non-woven fabric and the blank grid cloth in the detection step of the blank non-woven fabric and the blank grid cloth are multiple groups, and the area is the same, and the test is carried out under the same conditions respectively, and multiple groups _of m1 and m ₂ data; the m ₆ , m, m ₄ , m ₇ , m ₈ , m ₁ and m ₂ data in the step of calculating the resin insoluble content are based on the corresponding sets of data Arithmetic mean.

As a further preference of the present invention, the drying in the detection step of the sample and the comparative detection step is performed at a temperature of 75° C. to 85° C. for 2 hours.

As a further preference of the present invention, the step of calculating the resin insoluble content specifically includes:

Calculate the steps of the blank filter paper mass loss rate C ₀ :

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 7</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 8</span>}}}{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 7</span>}}}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 100</span>}\mathrm{<span\; class="notranslate">\; \%</span>}<span\; class="notranslate">\; ;</span>$

Calculate the steps of the blank non-woven fabric and the blank grid cloth mass loss rate _C1 :

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 100</span>}\mathrm{<span\; class="notranslate">\; \%</span>}<span\; class="notranslate">\; ;</span>$

And the step of calculating the insoluble content C _r of the resin in the sample:

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; \&lsqb;</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 6</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 5</span>}}<span\; class="notranslate">\; )</span>}{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 6</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}}}<span\; class="notranslate">\; \&rsqb;</span><span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 100</span>}\mathrm{<span\; class="notranslate">\; \%</span>}<span\; class="notranslate">\; ,</span>$

Wherein, m ₃ =m ₄ -m(1-C ₀ ), m ₅ =m ₆ (1-M _r )×C ₁ , and M _r is the resin content of the inner lining layer.

As a further preference of the present invention, the resin content M _r of the inner liner satisfies:

${\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}<span\; class="notranslate">\; ,</span>$

Wherein, n1 is the number of layers of non-woven fabric in the inner liner _of the bamboo composite pressure pipe, and _n2 is the number of layers of mesh cloth in the inner liner of the bamboo composite pressure pipe _; M0 is the surface density of the inner liner , M ₁ is the areal density of the single-layer non-woven fabric, M ₂ is the areal density of the single-layer mesh cloth, and the M ₀ , M ₁ and M ₂ are the inner lining layer, the single-layer mesh, respectively. The data obtained after drying one layer of non-woven fabric and the single-layer grid cloth at 75°C to 85°C for 2 hours.

As a further preference of the present invention, the m ₆ , m, m ₄ , m ₇ , m ₈ , m ₁ and m ₂ are all accurate to 0.1 mg.

As a further preference of the present invention, the extraction device is a Soxhlet extractor, which has a siphon; and when extracting in a water bath, the highest point of the filter paper is lower than the highest point of the siphon; The number of reflows per hour in the siphon is 6 to 10 times.

As a further preference of the present invention, the insoluble content _Cr is not less than 90%.

As a further preference of the present invention, n ₁ layers of blank nonwoven fabric and n ₂ layers of blank mesh cloth in the detection step of the blank nonwoven fabric and blank grid cloth, each layer of the blank nonwoven fabric and the blank grid cloth The area of the blank grid cloth is the same.

As a further preference of the present invention, m ₁ in the detection step of the blank non-woven fabric and the blank grid cloth is in the range of 0.8g to 1.2g.

Through the above technical scheme conceived by the present invention, compared with the prior art, the detection method is optimized due to the combination of the structure of the inner liner of the bamboo composite pressure pipe, so that the content of resin insolubles obtained by detection can be more direct and accurate. The performance of the lining layer can be accurately reflected, the result is stable and reliable, and it has a good effect on simplifying the actual operation of the detection process.

Since the inner liner of the bamboo composite pressure pipe uses non-woven fabrics (such as bamboo fiber non-woven fabrics) and mesh cloths in the preparation process, non-woven fabrics and mesh cloths will affect the final result of the insoluble resin; especially When the number of layers of non-woven fabric n ₁ and the number of mesh cloth layers n ₂ vary greatly, the results of resin insolubles will also fluctuate greatly, which will ultimately affect the evaluation of bamboo composite pressure pipes based on the parameters of resin insolubles. Determination of the performance of the lining layer. In the detection method of the present invention, the relevant parameters of the non-woven fabric or grid cloth are measured separately, so that the data of the insoluble content of the resin in the inner lining layer finally obtained is more accurate, and it is more beneficial to accurately determine the quality of the inner lining layer of the bamboo composite pressure pipe. quality. Further, considering that the bamboo composite pressure pipe needs to be able to withstand a certain pressure value, in order to ensure the overall quality of the bamboo composite pressure pipe, the insoluble content of the resin in the inner lining layer obtained by the detection method of the present invention should not be less than 90%; If the detected resin insoluble content is less than 90%, the quality of the inner liner of the bamboo composite pressure pipe cannot be guaranteed, and the pressure performance of the bamboo composite pressure pipe will be affected. The detection method in the present invention can be used for various types of bamboo composite pressure pipes (including bamboo winding composite pipes, bamboo sand composite pressure pipes, etc.), as long as the inner lining of the bamboo composite pressure pipes uses resin in the preparation process. In addition, according to the specific preparation process of the inner liner of the bamboo composite pressure pipe, it may not contain non-woven fabric or mesh fabric (ie, n ₁ =0 or/and n ₂ =0).

Before and after the extraction reaction in each step of the present invention, the extract (including sample, blank filter paper, blank non-woven fabric and grid cloth, etc.) Treat for 2 hours, and the temperature range can be further preferably 78°C to 82°C), which ensures that the initial conditions of each part of the extract are consistent; the drying temperature is lower than 100°C, which avoids excessive damage to the inner lining of the bamboo composite tube Mechanical properties, resulting in inaccurate results; by adding the loss test of blank non-woven fabric and blank grid cloth before and after extraction, and removing the corresponding losses of non-woven fabric and grid cloth in the final result calculation formula, the results are more accurate.

On the other hand, the present invention preferably calculates blank non-woven fabric (as bamboo fiber non-woven fabric), grid cloth mass loss rate (certainly, also can adopt to calculate this loss rate value by C ₀ ) by separate calculation, compares by C ₀ The method of calculating the loss rate value (if this calculation method is adopted, it is necessary to weigh the filter paper containing non-woven fabric and mesh cloth after the extraction in the step of "detection of non-woven fabric and mesh cloth". mass, and record this mass as m′, then Wherein, m ₂ =m ₁ -m'×(1-C ₀ ) is obtained by calculation, rather than direct measurement), due to the method of separately weighing the bamboo fiber non-woven fabric and grid cloth quality after extraction, making The result of the final resin insoluble content is more accurate. The filter paper in the step (2.1) of the present invention is the same as the filter paper in the step (1); the filter paper in the step (2.2) can be the same or different from the filter paper in the step (1).

In addition, the present invention preferably _defines the calculation method of the resin content M of the lining layer, and M _reflects the proportion of the resin in the lining layer. For different types of bamboo composite pressure pipes, because the composition of the lining layer may change, M The _r parameter can reduce the influence of other components in the lining layer except the resin, so as to accurately measure the insoluble content of the resin in the lining layer. Of course, under the premise that there is little difference in the inner lining structure of different types of bamboo composite pressure pipes, the value of M _r can also be directly specified (for example, M _r can be a constant value not greater than 1, such as 1, 0.8, etc.), to simplify the resin Calculation of insoluble fraction.

Description of drawings

Fig. 1 is the schematic flow chart of the method for detecting resin insoluble content in the inner liner of bamboo composite pressure pipe in the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not constitute a conflict with each other.

Example 1

Figure 1 shows a schematic flow chart of the method for detecting resin insoluble content in the inner liner of a bamboo composite pressure pipe.

On the bamboo composite pressure pipe with a nominal diameter of 800mm and a pressure rating of 0.8MPa, a section of pipe ring with a length of 50mm is cut, and then a sample with an arc length of 50mm is taken (in order to make the experimental results reflect the overall performance of the bamboo composite pressure pipe, it can be Samples with an arc length of 50 mm were cut from three different parts of the pipe ring, and the arithmetic mean of the results was taken as the final conclusion after testing respectively), and the inner lining layer was carefully peeled off with a blade on the above-mentioned 50 mm × 50 mm sample as sample. Cut out the bamboo fiber non-woven fabric and grid cloth used to make the lining layer respectively, the length × width (L × B) of each piece of bamboo fiber non-woven fabric and grid cloth is not less than 200mm × 150mm, and record The bamboo fiber non-woven fabric has a length L ₁ and a width B ₁ , and the grid cloth has a length L ₂ and a width B ₂ .

Next, put the inner liner, bamboo fiber non-woven fabric and grid cloth in a blast oven at 80°C±2°C for 2 hours, take them out, put them in a desiccator to cool to room temperature, and weigh them with an analytical balance. Record the weight W 1 of the inner lining layer, the weight W ₂ of the bamboo fiber non-woven fabric, and the weight W ₃ of the grid cloth, all _of which are accurate to 0.1 mg.

Calculate the mass M ₁ (g/m ² ) of the bamboo fiber non-woven fabric per unit area and the mass M ₂ (g/m ² ) of the grid cloth per unit area:

${\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; ,</span>$

${\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}}{{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; B</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; ;</span>$

In order to make the results accurate, in this example, three groups of bamboo fiber non-woven fabrics and grid cloths with different areas are taken to be dried together, weighed after drying, and M ₁ and M ₂ are calculated respectively according to the above formula, and the arithmetic mean value is taken As the mass per unit area of this bamboo fiber non-woven fabric and grid cloth, concrete test data are as follows:

Taking the arithmetic mean value: M ₁ =38.05g/m ² , M ₂ =57.81g/m ² , then the resin content M _r of the lining layer:

${\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 0.0025</span>}<span\; class="notranslate">\; \&times;</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{{\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 100</span>}\mathrm{<span\; class="notranslate">\; \%</span>}<span\; class="notranslate">\; ,</span>$

In the formula, n1 is the number of layers of bamboo fiber non _- woven fabric in the inner lining layer; _n2 is the number of layers of mesh cloth in the inner lining layer. In this embodiment, n ₁ =3, n ₂ =3. The above formula is The transformed form of , where M ₀ is the areal density of the lining layer.

The test data of the three groups of samples are as follows:

W ₁ (mg) M _r sample 1 5563.1 87.08% sample 2 5567.5 87.09% sample 3 5559.4 87.07%

Take the arithmetic mean value as the value of the resin content of the inner lining layer of the bamboo composite pressure pipe: M _r =87.08%.

The present embodiment 1 carries out substantially by the regulation of GB/T2576, but should add a blank experiment of making the raw material (bamboo fiber non-woven fabric and grid cloth) that lining layer is used, and its concrete method is as follows:

Put n ₁ = 3 layers of bamboo fiber non-woven fabric and n ₂ = 3 layers of grid cloth required for the inner lining of the bamboo composite pressure pipe with a nominal diameter of 800 mm and a pressure rating of 0.8 MPa into a drum at 80 °C ± 2 °C In the air oven for 2 hours, take it out and put it in a desiccator to cool to room temperature, combine the bamboo fiber non-woven fabric and grid cloth together, weigh 1g±0.2g with an analytical balance, record the weight, accurate to 0.1 mg, to ensure that the area of each layer of cloth is the same.

Blank bamboo fiber non-woven fabric, grid cloth mass loss rate C ₁ :

C ₁ =(m ₁ -m ₂ )/m ₁ ×100%,

In the formula, m ₁ is the mass of the blank bamboo fiber non-woven fabric and grid cloth before extraction, in milligrams (mg); m ₂ is the mass of the blank bamboo fiber non-woven fabric and grid cloth after extraction, in milligrams (mg) In order to make the result accurate, get three groups of bamboo fiber non-woven fabrics and grid cloth to test in the present embodiment, get the arithmetic mean value of three groups of data afterwards as final test result, concrete test data is as follows:

serial number m ₁ (mg) m ₂ (mg) C ₁ 1 978.6 978.3 0.030% 2 1024.8 1024.5 0.029% 3 1184.5 1184.1 0.033%

The arithmetic mean of the loss rate is 0.03%, that is, the mass loss rate of the blank bamboo fiber non-woven fabric and grid cloth is 0.031%.

Sample mass m ₃ after extraction:

m ₃ =m ₄ -m(1-C ₀ ),

In the formula, m ₃ is the mass of the sample after extraction, in milligrams (mg); m ₄ is the total mass of the filter paper tube or filter paper bag and residue after extraction, in milligrams (mg); m is the filter paper tube loaded with samples before extraction (including absorbent cotton) or filter paper bag mass, in milligrams (mg); C ₀ is the mass loss rate of blank filter paper;

Bamboo fiber non-woven fabric, grid cloth mass loss m ₅ :

m ₅ =m ₆ (1-M _r )×C ₁ ,

In the formula, m ₅ is the mass loss of bamboo fiber non-woven fabrics and grid cloth, in milligrams (mg); m ₆ is the mass of the sample before extraction, in milligrams (mg); M _r is the resin content of the inner lining layer, C ₁ is blank bamboo fiber non-woven fabric, grid cloth mass loss rate;

Insoluble resin content C _r of inner lining layer:

${\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; \&lsqb;</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 6</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 5</span>}}<span\; class="notranslate">\; )</span>}{{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; 6</span>}}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; m</span>}}_{\mathrm{<span\; class="notranslate">\; r</span>}}}<span\; class="notranslate">\; \&rsqb;</span><span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 100</span>}\mathrm{<span\; class="notranslate">\; \%</span>}<span\; class="notranslate">\; ,</span>$

In the formula, _Cr is the insoluble content of resin in the lining layer; m ₆ is the mass of the sample before extraction, in milligrams (mg); m ₃ is the mass of the sample after extraction, in milligrams (mg); m ₅ is The mass loss of bamboo fiber non-woven fabric and grid cloth is in milligrams (mg); M _r is the resin content of the inner lining layer.

according to the formula Calculate the blank filter paper loss rate, where m ₇ is the quality before the blank filter paper extraction, m ₈ is the quality after the blank filter paper extraction, the specific test data are as follows:

serial number m ₇ (mg) m ₈ (mg) C ₀ 1 1381.6 1352.4 2.113% 2 1380.2 1352.6 2.000% 3 1381.0 1353.4 2.000%

The arithmetic mean of the loss rate is 2.038%, that is, the mass loss rate of the blank filter paper is 2.038%.

Three 50mm*50mm samples of the bamboo composite pressure pipe with a nominal diameter of 800mm and a pressure rating of 0.8MPa were subjected to extraction tests. The specific test data are as follows:

m (mg) m ₄ (mg) m ₃ (mg) m ₆ (mg) m ₅ (mg) C _r sample 1 1381.6 6458.9 5105.5 5563.1 0.2 90.56% sample 2 1380.2 6457.3 5105.2 5567.5 0.2 90.47% sample 3 1381.0 6458.1 5105.2 5559.4 0.2 90.62%

Taking its arithmetic mean value as 90.55%, that is, the insoluble content of the resin in the lining layer of the bamboo composite pressure pipe is 90.55%, greater than 90%, and meets the requirements.

The places not described in detail in the above embodiments are all prior art, for example, refer to GB/T2576. Although according to the application conditions of the bamboo composite pressure pipe, the requirements for the insoluble content of the resin in the inner lining will change, but generally the insoluble content of the resin in the inner lining of the bamboo composite pressure pipe should not be less than 90%.

It is easy for those skilled in the art to understand that the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, All should be included within the protection scope of the present invention.

Claims (10)

1. detect a method for resin insoluble matter content in bamboo composite pressure pipe inner liner, it is characterized in that, comprise the detecting step of sample, contrast detecting step and calculate resin insoluble matter content step,

Wherein, the detecting step of described sample comprises:

Strip bamboo composite pressure pipe a part tube wall on inner liner as sample, the inner liner of this bamboo composite pressure pipe has n ₁layer nonwoven fabrics and n ₂layer grid cloth; Described sample drying is dry, and the quality weighing this sample after cooling is designated as m ₆; Then get filter paper, and the quality weighing this filter paper is designated as m, then states sample with this filter paper packet residence, then the described filter paper that described sample is housed is put into extraction equipment, add acetone and extract; After extraction, it is taken out in the lump, drain post-drying and be dried to constant weight, then cool the filter paper that this sample is housed after being namely extracted, weigh the gross mass that the filter paper of this sample is housed after described extraction, and remember that this quality is m ₄;

Described contrast detecting step comprises the detecting step of blank filter paper detecting step and blank nonwoven fabrics and blank grid cloth,

Wherein, described blank filter paper detecting step comprises:

Get blank filter paper separately, described blank filter paper is identical with the filter paper kind in the detecting step of described sample, by this blank filter paper bake drying, weighs its quality, remember that this quality is m after cooling ₇, then this blank filter paper is put into extraction equipment, adds acetone and extract; After extraction, take out this blank filter paper, drain post-drying and be dried to constant weight, then cool the blank filter paper after being namely extracted, weigh the quality of the blank filter paper after described extraction, and remember that this quality is m ₈;

The detecting step of described blank nonwoven fabrics and blank grid cloth comprises:

Get n separately ₁the blank nonwoven fabrics of layer and n ₂the blank grid cloth of layer, described blank nonwoven fabrics is identical with the number of plies with the kind of grid cloth with nonwoven fabrics in the bamboo composite pressure pipe inner liner in the detecting step of described sample with the number of plies with the kind of described blank grid cloth; By described n ₁the blank nonwoven fabrics of layer and described n ₂the blank grid cloth bake drying of layer, weighs its quality after cooling, and remembers that this quality is m ₁; By described n ₁the blank nonwoven fabrics of layer and n ₂the blank grid cloth filter paper of layer encases the filter paper being formed and blank nonwoven fabrics and blank grid cloth are housed, and the described filter paper that blank nonwoven fabrics and blank grid cloth are housed is put into extraction equipment, adds acetone and extract; After extraction, it is taken out in the lump, drain post-drying and be dried to constant weight, then the filter paper that blank nonwoven fabrics and blank grid cloth are housed after being namely extracted is cooled, take out the blank nonwoven fabrics after extraction wherein and blank grid cloth, and weigh the quality of the blank nonwoven fabrics after described extraction and blank grid cloth, remember that this quality is m ₂;

Described calculating resin insoluble matter content step comprises:

According to the m in the detecting step of described sample ₆, m, m ₄and the m in described contrast detecting step ₇, m ₈, m ₁, m ₂draw resin insoluble matter content in this bamboo composite pressure pipe inner liner.

2. detect the method for resin insoluble matter content in bamboo composite pressure pipe inner liner as claimed in claim 1, it is characterized in that, sample in the detecting step of described sample is multiple, and be the sample that multiple areas of stripping at described bamboo composite pressure pipe different parts are identical, be test under the same conditions respectively, obtain and organize m more ₆, m and m ₄data; Blank filter paper in described blank filter paper detecting step is multiple, and area is identical, is test under the same conditions respectively, obtains and organizes m more ₇and m ₈data; Blank nonwoven fabrics in the detecting step of described blank nonwoven fabrics and blank grid cloth and blank grid cloth are many groups, and area is identical, are test under the same conditions respectively, obtain and organize m more ₁and m ₂data; The m of resin insoluble matter content foundation in described calculating resin insoluble matter content step ₆, m, m ₄, m ₇, m ₈, m ₁and m ₂data are the arithmetic mean of each self-corresponding multi-group data.

3. detect the method for resin insoluble matter content in bamboo composite pressure pipe inner liner as claimed in claim 1, it is characterized in that, the oven dry in the detecting step of described sample and described contrast detecting step is all process 2 hours at the temperature of 75 DEG C ~ 85 DEG C.

4. detect the method for resin insoluble matter content in bamboo composite pressure pipe inner liner as claimed in claim 1, it is characterized in that, described calculating resin insoluble matter content step specifically comprises:

Calculate described blank filter paper mass loss rate C ₀step:

$C_0=\frac{m_7-m_8}{m_7}\&times;100\%;$

Calculate described blank nonwoven fabrics and blank grid cloth mass loss rate C ₁step:

$C_1=\frac{n_h-m_2}{m_1}\&times;100\%;$

And calculate the insoluble matter content C of resin in described sample _rstep:

$C_r=\&lsqb;1-\frac{m_6-(m_3+m_5)}{m_6\&times;M_r}\&rsqb;\&times;100\%,$

Wherein, m ₃=m ₄-m (1-C ₀), m ₅=m ₆(1-M _r) × C ₁, M _rfor inner liner resin content.

5. detect the method for resin insoluble matter content in bamboo composite pressure pipe inner liner as claimed in claim 4, it is characterized in that, described inner liner resin content M _rmeet:

$M_r=\frac{M_0-(n_1\&times;M_1+n_2\&times;M_2)}{M_0},$

Wherein, n ₁for the number of plies of nonwoven fabrics in this bamboo composite pressure pipe inner liner, n ₂for the number of plies of grid cloth in this bamboo composite pressure pipe inner liner; M ₀for the surface density of this inner liner, M ₁for the surface density of nonwoven fabrics described in individual layer, M ₂for the surface density of grid cloth described in individual layer, described M ₀, M ₁and M ₂be respectively described inner liner, described single-layer nonwoven and described single layer mesh cloth at 75 DEG C ~ 85 DEG C, dry the data obtained after 2 hours.

6. detect the method for resin insoluble matter content in bamboo composite pressure pipe inner liner as claimed in claim 1, it is characterized in that, described m ₆, m, m ₄, m ₇, m ₈, m ₁and m ₂all be accurate to 0.1mg.

7. detect the method for resin insoluble matter content in bamboo composite pressure pipe inner liner as claimed in claim 1, it is characterized in that, described extraction equipment is apparatus,Soxhlet's, and this extraction equipment has U trap; And when carrying out water-bath extraction, the peak of described filter paper is lower than described siphonal peak; Extract reflow's cycle per hour in described U trap is 6 times ~ 10 times.

8. detect the method for resin insoluble matter content in bamboo composite pressure pipe inner liner as claimed in claim 1, it is characterized in that, described insoluble matter content C _rbe not less than 90%.

9. as described in claim 1-8 any one, detect the method for resin insoluble matter content in bamboo composite pressure pipe inner liner, it is characterized in that, the n in the detecting step of described blank nonwoven fabrics and blank grid cloth ₁the blank nonwoven fabrics of layer and n ₂the blank grid cloth of layer, every layer of described blank nonwoven fabrics is all identical with the area of described blank grid cloth.

10. as described in claim 1-9 any one, detect the method for resin insoluble matter content in bamboo composite pressure pipe inner liner, it is characterized in that, the m in the detecting step of described blank nonwoven fabrics and blank grid cloth ₁within the scope of 0.8g ~ 1.2g.