CN115028946A - CPVC (chlorinated polyvinyl chloride) pipe for high-pollution-resistant high-temperature organic wastewater and preparation method thereof - Google Patents

Abstract

The invention discloses a CPVC (chlorinated polyvinyl chloride) pipe for high-pollution-resistant high-temperature organic wastewater and a preparation method thereof, wherein the CPVC pipe comprises the following components in parts by weight: 100 parts of CPVC resin, 0.2-2.0 parts of heat stabilizer, 1-5 parts of lubricant, 5-20 parts of impact modifier, 1-2 parts of antioxidant and 3-10 parts of load type anti-fouling modifier; the supported anti-fouling modifier is SMA sodium salt supported hydrotalcite. According to the CPVC pipe disclosed by the invention, the antifouling performance is obviously improved through the supported antifouling modifier, the enrichment of microbial pollutants on the inner wall of the CPVC pipe is avoided, the maintenance cost of the CPVC pipe is reduced, and the CPVC pipe has a wide application prospect.

Description

CPVC (chlorinated polyvinyl chloride) pipe for high-pollution-resistant high-temperature organic wastewater and preparation method thereof

Technical Field

The invention belongs to the technical field of modified high polymer materials, and particularly relates to a CPVC (chlorinated polyvinyl chloride) pipe for high-pollution-resistant high-temperature organic wastewater and a preparation method thereof.

Background

Chlorinated polyvinyl chloride (CPVC) is a chlorinated product of polyvinyl chloride (PVC), theoretically, the maximum chlorine content of the chlorinated polyvinyl chloride can reach 73.2%, and the chlorinated polyvinyl chloride has more excellent physical and chemical properties than the polyvinyl chloride due to the increase of the chlorine content, and particularly, the high temperature resistance, the aging resistance, the corrosion resistance, the weather resistance and the flame retardant self-extinguishing property are greatly improved compared with the PVC. The maximum service temperature can reach 110 ℃, which is much higher than that of common rigid polyvinyl chloride. Therefore, the CPVC pipe is widely used for pipeline transportation of hot water, corrosive liquid and corrosive gas, such as high-temperature organic wastewater generated in the wine industry, saturated brine in the chlor-alkali industry, liquid caustic soda, hydrochloric acid and other special media. However, CPVC is very hydrophobic and easily adsorbs contaminants, accelerating the contamination of pipes and increasing the transport resistance of pipes. Particularly, in winery sewage with the cod value of over 12000mg/L, a large amount of microbial pollutants are easily enriched in CPVC pipes, so that the pipe circulation is reduced, the running resistance is increased, and the maintenance cost is increased. Therefore, the anti-pollution performance of the CPVC pipe needs to be improved.

At present, the modification of the CPVC pipe is mainly focused on the modification of the CPVC pipe based on its processability, high temperature resistance, etc., and the research on the anti-fouling performance of the CPVC pipe is less. Patent CN107216592A discloses a method for preparing a CPVC pipe with a photocatalytic self-cleaning function, wherein the self-cleaning property of the CPVC pipe is realized mainly through the photocatalytic property and antibacterial property of nano titanium dioxide. However, in the field of sewage treatment membranes, a number of methods for modifying the fouling resistance are available. Literature research shows that the anti-pollution performance of the CPVC sewage treatment membrane can be improved by increasing the hydrophilicity of the CPVC sewage treatment membrane. The main principle lies in that after CPVC material hydrophilicity is improved, the interaction force with water is greater than the interaction force with microbial adhesion protein, and then a layer of water layer protective layer is formed on the surface of the CPVC material, so that the surface of the CPVC material can not be found by microbes and bacteria in water, and the anti-pollution performance of the CPVC material can be improved. Therefore, high antifouling performance of CPVC pipe can also be achieved by improving its hydrophilicity. However, most of the current hydrophilic modification methods for sewage treatment membranes are carried out in a solvent, and are not suitable for the CPVC melt extrusion pipe process. Therefore, the development of a hydrophilic modification method for preparing the high-pollution-resistance CPVC pipe is urgently needed to meet the requirement of high-temperature organic wastewater pipeline transportation.

Disclosure of Invention

This section is for the purpose of summarizing some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. In this section, as well as in the abstract and the title of the invention of this application, simplifications or omissions may be made to avoid obscuring the purpose of the section, the abstract and the title, and such simplifications or omissions are not intended to limit the scope of the invention.

The present invention has been made keeping in mind the above and/or other problems occurring in the prior art.

One of the purposes of the invention is to provide a CPVC pipe for high-temperature organic wastewater with high anti-fouling performance, wherein the anti-fouling performance of the CPVC pipe is remarkably improved by a load type anti-fouling modifier, so that the enrichment of microbial pollutants on the inner wall of the CPVC pipe is avoided, the maintenance cost of the CPVC pipe is reduced, and the CPVC pipe has a wide application prospect.

In order to solve the technical problems, the invention provides the following technical scheme: the CPVC pipe for the high-pollution-resistance high-temperature organic wastewater comprises the following components in parts by weight: 100 parts of CPVC resin, 0.2-2.0 parts of heat stabilizer, 1-5 parts of lubricant, 5-20 parts of impact modifier, 1-2 parts of antioxidant and 3-10 parts of load type anti-fouling modifier;

the supported anti-fouling modifier is SMA sodium salt supported hydrotalcite.

As a preferred scheme of the CPVC pipe for high-pollution-resistant high-temperature organic wastewater, the CPVC pipe comprises the following components in percentage by weight: the chlorine content of the CPVC resin is 65-70%.

As a preferred scheme of the CPVC pipe for high-pollution-resistant high-temperature organic wastewater, the CPVC pipe comprises the following components in percentage by weight: the heat stabilizer is one or more of butyl tin stabilizer, methyl tin mercaptide stabilizer, zeolite and C6-C12 metal carboxylate.

As a preferred scheme of the CPVC pipe for high-pollution-resistant high-temperature organic wastewater, the CPVC pipe comprises the following components in percentage by weight: the lubricant is one or more of calcium stearate, paraffin, erucamide, Fischer-Tropsch wax, polyethylene wax and oxidized polyethylene wax.

As a preferred scheme of the CPVC pipe for high-pollution-resistant high-temperature organic wastewater, the CPVC pipe comprises the following components in percentage by weight: the impact modifier is one or more of methyl methacrylate-butadiene-styrene copolymer, chlorinated polyethylene, acrylate rubber and acrylonitrile-butadiene-styrene.

As a preferred scheme of the CPVC pipe for high-pollution-resistant high-temperature organic wastewater, the CPVC pipe comprises the following components in percentage by weight: the antioxidant comprises one or more of antioxidant 1010, antioxidant 300, antioxidant 264, antioxidant 2246 and antioxidant 1076.

It is another object of the present invention to provide a method for preparing CPVC pipe for high temperature organic wastewater with high antifouling property, which comprises,

providing a supported antifouling modifier;

the material components are evenly mixed according to the proportion in claim 1 and then are extruded and molded to obtain the material.

As a preferred scheme of the preparation method of the CPVC pipe for high-pollution-resistant high-temperature organic wastewater, the method comprises the following steps: the preparation method of the supported anti-fouling modifier comprises the step of loading SMA sodium salt on hydrotalcite to obtain the supported anti-fouling modifier.

As a preferable scheme of the preparation method of the CPVC pipe for high-pollution-resistant high-temperature organic wastewater, the method comprises the following steps: the method for loading the SMA sodium salt on the hydrotalcite specifically comprises the following steps,

adding hydrotalcite into absolute ethyl alcohol, stirring, and stirring in a water bath at 70 ℃ for 1 h;

dissolving SMA sodium salt in deionized water at 80 ℃, adding the solution, adjusting the pH to 4 with dilute nitric acid with the pH of 2, and reacting for 8 hours;

and after the reaction is finished, cooling, filtering, washing, drying and grinding to obtain the SMA sodium salt loaded hydrotalcite.

As a preferred scheme of the preparation method of the CPVC pipe for high-pollution-resistant high-temperature organic wastewater, the method comprises the following steps: the mass/mol ratio of the hydrotalcite to the SMA sodium salt is 1: 2 to 6.

As a preferred scheme of the preparation method of the CPVC pipe for high-pollution-resistant high-temperature organic wastewater, the method comprises the following steps: the hydrotalcite is magnesium aluminum carbonate type hydrotalcite.

Compared with the prior art, the invention has the following beneficial effects:

according to the invention, the replacement of carbonate in magnesium aluminum carbonate type hydrotalcite is utilized, and the hydrophilic modifier SMA sodium salt is loaded in the hydrotalcite to obtain the hydrophilic modifier which can be uniformly dispersed in the CPVC, so that the hydrophilicity of the CPVC is improved, the anti-fouling performance of the CPVC pipe is greatly improved, the problem that microbial pollutants are easy to enrich in the CPVC pipe during high-temperature organic wastewater conveying is solved, and the maintenance cost of the CPVC pipe is obviously reduced. Meanwhile, the hydrotalcite is an auxiliary heat stabilizer of the CPVC, so that the heat stability of the CPVC can be further improved, and the processing window of the CPVC is widened. The preparation process is simple, has low requirements on equipment, and has wide application prospect.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the description below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive labor. Wherein:

FIG. 1 is a schematic diagram of the mechanism of the CPVC pipe for high-temperature organic wastewater with high antifouling property of the invention;

FIG. 2 is a graph comparing the water contact angles of example 1 of the present invention and comparative example 1.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, specific embodiments thereof are described in detail below with reference to examples of the specification.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.

Furthermore, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one implementation of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

The raw materials used in the examples were all purchased commercially unless otherwise specified.

Example 1

The embodiment provides a preparation method of a CPVC (chlorinated polyvinyl chloride) pipe for high-pollution-resistant high-temperature organic wastewater, which mainly comprises the following steps:

(1) preparing a load type anti-fouling modifier:

adding 5g of magnesium-aluminum carbonate type hydrotalcite into 250ml of absolute ethyl alcohol, and stirring for 1h in a water bath at 70 ℃;

dissolving 20g of SMA sodium salt in deionized water at 80 ℃, adding the dissolved SMA sodium salt into the solution, adjusting the pH to 4 by using dilute nitric acid with the pH of 2, and reacting for 8 hours;

and after the reaction is finished, cooling, filtering, washing with 50% absolute ethyl alcohol solution and deionized water, drying at 60 ℃, and grinding to obtain the SMA sodium salt loaded hydrotalcite.

(2) The formula is as follows: in the present example, the raw materials and the compounding ratio used are shown in table 1;

(3) preparing a high anti-fouling CPVC pipe: the CPVC pipe material for high-pollution-resistant high-temperature organic wastewater is obtained by uniformly mixing the raw material components according to the table 1 and then carrying out extrusion molding.

TABLE 1

Example 2

The present example differs from example 1 in the type of CPVC resin used in the formulation, and the procedure is the same as the procedures (1) to (3) of example 1 with specific reference to table 2.

TABLE 2

Example 3

This example differs from example 1 in the amount of impact modifier used in the formulation, and is the same as example 1 in steps (1) to (3) with specific reference to Table 3.

TABLE 3

Example 4

This example differs from example 1 in the amount of heat stabilizer used in the formulation, and the procedure is the same as in steps (1) to (3) of example 1, with specific reference to table 4.

TABLE 4

Example 5

This example differs from example 1 in the amount of lubricant used in the formulation, and specifically, with reference to table 5, the procedure is the same as in steps (1) to (3) of example 1.

TABLE 5

Comparative example 1

The difference from example 1 is that hydrotalcite supported on no SMA sodium salt was added, and only unmodified hydrotalcite was added, and specifically referring to table 6, the procedure was the same as in steps (1) to (3) of example 1:

TABLE 6

Comparative example 2

The difference from example 1 is that the content of the SMA sodium salt-supported hydrotalcite is different, and specifically referring to table 7, the procedure is the same as the procedures (1) to (3) of example 1:

TABLE 7

Comparative example 3

The difference from example 1 is that the SMA sodium salt supported hydrotalcite content is different, and specifically referring to table 8, the procedure is the same as steps (1) to (3) of example 1:

TABLE 8

Comparative example 4

The difference from the embodiment 1 is that the loading capacity of the SMA sodium salt in the SMA sodium salt loaded hydrotalcite is different, and the preparation method of the loaded anti-fouling modifier comprises the following steps:

(1) adding 5g of magnesium aluminum carbonate type hydrotalcite into 250ml of absolute ethyl alcohol, and stirring for 1h in a water bath at 70 ℃.

(2) Dissolving 5g of SMA sodium salt in deionized water at 80 ℃, adding the dissolved SMA sodium salt into the solution in the step (1), adjusting the pH to 4 by using dilute nitric acid with the pH of 2, and reacting for 8 hours.

(3) And after the reaction is finished, cooling, filtering, washing with 50% absolute ethyl alcohol solution and deionized water, drying at 60 ℃, and grinding to obtain the SMA sodium salt loaded hydrotalcite.

The procedure for the production of the CPVC pipe was the same as in steps (1) to (3) of example 1.

Comparative example 5

The difference from the embodiment 1 is that the loading capacity of the SMA sodium salt in the SMA sodium salt loaded hydrotalcite is different, and the preparation method of the loaded anti-fouling modifier comprises the following steps:

(1) adding 5g of magnesium aluminum carbonate type hydrotalcite into 250ml of absolute ethyl alcohol, and stirring for 1h in a water bath at 70 ℃.

(2) Dissolving 30g of SMA sodium salt in deionized water at 80 ℃, adding the dissolved SMA sodium salt into the solution in the step (1), adjusting the pH to 4 by using dilute nitric acid with the pH of 2, and reacting for 8 hours.

(3) And after the reaction is finished, cooling, filtering, washing with 50% absolute ethyl alcohol solution and deionized water, drying at 60 ℃, and grinding to obtain the SMA sodium salt loaded hydrotalcite.

The procedure for the production of the CPVC pipe was the same as in steps (1) to (3) of example 1.

Comparative example 6

The difference from example 1 is that, without addition of an anti-fouling modifier, the procedure is the same as in steps (1) to (3) of example 1, with specific reference to table 9:

TABLE 9

According to GB/T18993.2-2020 part 2 of a polyvinyl chloride for Cold and Hot (PVC-C) pipe System: the pipe standard tests the density, Vicat softening temperature, longitudinal shrinkage, tensile yield stress, drop weight impact test, thermal stability in hydrostatic state, light transmittance and the like of the obtained CPVC pipe as basic physical performance parameters for using the pipe. Wherein the content of the first and second substances,

testing the density of the obtained CPVC pipe according to the GB/T8802-2001 standard, wherein the index requirement is 1450-1650 kg/m ³ The test results are shown in Table 10;

the Vicat softening temperature of the obtained CPVC pipe is tested according to the GB/T8802-2001 standard, the heating rate is 50 ℃/h, the load is 50N, the index requirement is not less than 110 ℃, and the test results are shown in Table 10;

testing the longitudinal shrinkage of the obtained CPVC pipe according to the GB/T6671-2001 standard, wherein the test temperature is 150 ℃, the test time is 1h, the index requirement is less than or equal to 5%, and the test results are shown in a table 10;

testing the tensile yield stress of the obtained CPVC pipe according to the GB/T8804.2-2003 standard, wherein the tensile speed is 5mm/min, the index requirement is not less than 50MPa, and the test result is shown in Table 10;

performing drop hammer impact test on the obtained CPVC pipe according to the GB/T14152-2001 standard, wherein the test temperature is 0 ℃, the index requirement is less than or equal to 10 percent, and the test results are shown in a table 10;

performing a thermal stability test on the obtained CPVC pipe in a hydrostatic state according to GB/T6111-2018 standard, wherein the test temperature is 95 ℃, the test time is 8760h, the hydrostatic stress is 3.6MPa, and the index requirements are as follows: no cracking and no penetration, and the test results are shown in table 10;

the obtained CPVC pipe is subjected to a light transmittance test according to the GB/T21300-2007 standard, the index requirement is less than or equal to 0.2%, and the test result is shown in a table 10.

In addition, compared with the common CPVC pipe, the CPVC pipe provided by the invention has the characteristic of high stain resistance, and the related performance indexes are characterized by adopting the following detection modes:

testing the water contact angle of the obtained CPVC pipe according to the GB/T30693-2014 standard, detecting the improvement condition of the stain-resistant modifier of the SMA sodium salt loaded hydrotalcite on the hydrophilicity of the CPVC pipe, and the test result is shown in Table 10;

the anti-fouling performance is as follows: high-temperature organic wastewater discharged from a winery is taken as test sewage, the CPVC pipe is soaked in the sewage for 8760h, the change condition of surface elements of the CPVC pipe before and after soaking is inspected by X-ray photoelectron spectroscopy (XPS), and the test results are shown in Table 10.

TABLE 10

A comparison graph of water contact angles of the CPVC pipe prepared in example 1 and the CPVC pipe prepared in comparative example 1 is shown in fig. 1, and it can be seen that the water contact angle of the CPVC pipe prepared in example 1 is significantly smaller than that of comparative example 1, so that microbial pollutants are prevented from attaching to the pipe wall and being enriched, and the anti-fouling capability of the CPVC pipe is improved.

As can be seen from Table 10, the CPVC can meet the use requirements of pipes when the contents (types) of the CPVC resin, the heat stabilizer, the lubricant and the impact modifier in the formula are changed. However, only when the hydrotalcite loaded by the SMA sodium salt is added, the antifouling property of the CPVC pipe can be obviously improved. However, the higher the addition amount of the supported antifouling modifier is, the better, the higher the addition amount of the supported antifouling modifier is, the higher the supported antifouling modifier is, and the antifouling property is adversely affected, because the supported antifouling modifier is agglomerated when the content is too high, and the effectiveness of hydrophilic modification is reduced.

When the loading amount of the SMA sodium salt in the SMA sodium salt loaded hydrotalcite is lower, the anti-fouling performance of the CPVC pipe is obviously reduced, the loading amount of the SMA sodium salt in the SMA sodium salt loaded hydrotalcite is properly increased, and the improvement of the anti-fouling performance of the CPVC pipe is facilitated.

As can be seen from example 1 and comparative example 6, when no SMA sodium salt supported hydrotalcite was added to the formulation, the antifouling performance of the CPVC pipe was significantly reduced. In addition, the overall performance of the CPVC pipe is also reduced, probably because hydrotalcite is an auxiliary heat stabilizer for CPVC and the absence of hydrotalcite reduces the thermal stability during CPVC extrusion processing.

The SMA sodium salt is a hydrophilic modifier, is easy to agglomerate due to strong intermolecular interaction during melt extrusion processing, is difficult to disperse uniformly, has poor hydrophilic modification effect, and is mainly used in the solution processing process. The invention is based on the replaceability of carbonate anions in hydrotalcite, and the supported anti-fouling modifier is prepared by loading SMA sodium salt in the hydrotalcite. The hydrotalcite can obviously reduce the interaction among SMA molecules, thereby improving the dispersibility of the hydrotalcite in CPVC and furthest playing the role of hydrophilic modification of SMA. In the water cooling process of the CPVC pipe, the anti-fouling modifier migrates to the pipe wall due to the hydrophilicity of SMA in the load-type anti-fouling modifier, a water layer protective layer is formed at the pipe wall, and microbial pollutants are prevented from being attached to the pipe wall to be enriched, so that the anti-fouling capability of the CPVC pipe is improved. In addition, the hydrotalcite has the function of absorbing compounds such as hydrogen chloride and the like besides bearing the SMA sodium salt, so that the thermal stability of the CPVC can be further improved, the processing window of the CPVC is widened, and the comprehensive performance of the CPVC is improved.

It should be noted that the above-mentioned embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the claims of the present invention.

Claims (10)

1. The utility model provides a CPVC pipe for high anti-soil high temperature organic waste water which characterized in that: the paint comprises the following components in parts by weight: 100 parts of CPVC resin, 0.2-2.0 parts of heat stabilizer, 1-5 parts of lubricant, 5-20 parts of impact modifier, 1-2 parts of antioxidant and 3-10 parts of load type anti-fouling modifier;

the supported anti-fouling modifier is SMA sodium salt supported hydrotalcite.

2. A CPVC pipe for high temperature organic waste water with high fouling resistance as claimed in claim 1, wherein: the chlorine content of the CPVC resin is 65-70%.

3. A CPVC pipe for high temperature organic waste water with high antifouling property as claimed in claim 1 or 2, wherein: the heat stabilizer is one or more of butyl tin stabilizer, methyl tin mercaptide stabilizer, zeolite and C6-C12 metal carboxylate.

4. A CPVC pipe for high temperature organic waste water with high anti-fouling properties as claimed in claim 3, wherein: the lubricant is one or more of calcium stearate, paraffin, erucamide, Fischer-Tropsch wax, polyethylene wax and oxidized polyethylene wax.

5. A CPVC pipe for high temperature organic waste water with high dirt resistance as claimed in any one of claims 1, 2 and 4, wherein: the impact modifier is one or more of methyl methacrylate-butadiene-styrene copolymer, chlorinated polyethylene, acrylate rubber and acrylonitrile-butadiene-styrene.

6. A CPVC pipe for high temperature organic waste water with high dirt resistance as claimed in any one of claims 1, 2 and 4, wherein: the antioxidant comprises one or more of antioxidant 1010, antioxidant 300, antioxidant 264, antioxidant 2246 and antioxidant 1076.

7. A preparation method of a CPVC pipe for high-temperature organic wastewater with high antifouling property as claimed in any claim 1 to 6, which is characterized in that: comprises the steps of (a) preparing a mixture of a plurality of raw materials,

providing a supported antifouling modifier;

the material components are evenly mixed according to the proportion in claim 1 and then are extruded and molded to obtain the material.

8. A method of making a CPVC pipe for high temperature organic waste water that is highly resistant to fouling as claimed in claim 7, wherein: the preparation method of the supported anti-fouling modifier comprises the step of loading SMA sodium salt on hydrotalcite to obtain the supported anti-fouling modifier.

9. A method for preparing a CPVC pipe used for high temperature organic waste water with high anti-pollution performance as claimed in claim 7 or 8, wherein: the method for loading the SMA sodium salt on the hydrotalcite specifically comprises the following steps,

adding hydrotalcite into absolute ethyl alcohol, stirring, and stirring in a water bath at 70 ℃ for 1 h;

dissolving SMA sodium salt in deionized water at 80 ℃, adding the solution, adjusting the pH to 4 with dilute nitric acid with the pH of 2, and reacting for 8 hours;

and after the reaction is finished, cooling, filtering, washing, drying and grinding to obtain the SMA sodium salt loaded hydrotalcite.

10. A method for preparing a CPVC pipe for high temperature organic waste water with high anti-fouling properties as claimed in claim 9, wherein: the mass ratio of the hydrotalcite to the SMA sodium salt is 1: 2 to 6.

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