Vinyl-terminated polyether copolymerized modified PVC (Polyvinyl Chloride) resin as well as preparation method and application thereof

Abstract

The invention provides vinyl-terminated polyether copolymerized modified PVC (polyvinyl chloride) resin as well as a preparation method and application thereof. The modified PVC resin is prepared by polymerizing the following raw materials in parts by weight: 30 to 40 parts of vinyl chloride monomer, 1.5 to 3.0 parts of vinyl-terminated polyether, 0.01 to 0.02 part of initiator, 0.2 to 0.4 part of dispersing agent and 50 to 70 parts of dispersing medium. Long-chain-terminated vinyl polyether is added for internal toughening, covalent bonds are combined with PVC, meanwhile, a long side group structure is designed and utilized for increasing the distance between PVC molecular chains, reducing the interaction force between the molecular chains, promoting the flowability of the PVC chains, reducing the glass transition temperature of PVC and improving the toughening capacity of the modified PVC resin; the inorganic filler, the foaming agent, the stabilizing agent and the lubricating agent are added and then extruded through a screw extruder, the profile is obtained, and the steel-plastic co-extrusion micro-foaming profile for doors and windows has wide application prospects in the field of steel-plastic co-extrusion micro-foaming profiles for doors and windows.

Description

Technical Field

[0001] The present invention relates to the technical field of polyvinyl chloride preparation, and particularly relates to a modified PVC resin obtained by copolymerization of terminal vinyl polyether, a preparation method thereof, and an application thereof. Background Art

[0002] Polyvinyl chloride (PVC), as the third-largest general-purpose plastic in the world by production volume, is widely used in building materials such as doors and windows. However, rigid PVC is a brittle material and is very sensitive to notches. During the processing process, defects will occur when a high amount of calcium powder is filled, resulting in poor toughness and low elongation at break of the product, and cracking and other problems are likely to occur during use. To improve this situation, external toughening agents are usually used. However, the use of external toughening agents will cause the situation of small molecule migration, resulting in a decrease in the service life. Therefore, there is still room for optimization. Summary of the Invention

[0003] In view of the above deficiencies of the prior art, the purpose of the present invention is to provide a modified PVC resin obtained by copolymerization of terminal vinyl polyether and a preparation method thereof, aiming to solve the deficiencies of externally toughened PVC. The terminal vinyl polyether chemically modified PVC resin provided by the present application can overcome the disadvantages of easy migration and volatilization of external toughening agents, increase the duration of the toughening effect, and can improve the fracture toughness, water resistance, and mechanical properties of PVC products.

[0004] Specifically, the present invention provides the following technical solutions: In a first aspect of the present invention, there is provided a modified PVC resin obtained by copolymerization of terminal vinyl polyether, which is polymerized from the following raw materials: 30 - 40 parts by weight of vinyl chloride monomer, 1.5 - 3.0 parts by weight of terminal vinyl polyether, 0.01 - 0.02 parts by weight of initiator, 0.2 - 0.4 parts by weight of dispersant, 50 - 70 parts by weight of dispersion medium.

[0005] As a preferred embodiment of the present invention, the initiator is selected from one or more of IPP, benzoyl peroxide, azodiisobutyronitrile, azodiisovaleronitrile, and ammonium persulfate.

[0006] As a preferred embodiment of the present invention, the dispersant is one of PVA or sodium dodecylbenzenesulfonate.

[0007] As a preferred embodiment of the present invention, the dispersion medium is deionized water.

[0008] As a preferred embodiment of the present invention, the macromonomer of the terminal vinyl polyether includes polyether polyol, isophorone diisocyanate (IPDI) and a functional monomer. One end of the functional monomer contains a vinyl group, the other end contains a hydroxyl group, and the middle is a carbon chain.

[0009] As a preferred embodiment of the present invention, the molecular weight of the polyether polyol in the macromonomer of the terminal vinyl polyether is 400 - 5000 g / mol, and the functionality is one or more of bifunctional or trifunctional.

[0010] As a preferred embodiment of the present invention, the isocyanate in the macromonomer of the terminal vinyl polyether is selected from IPDI, and two-step functionalization is carried out by utilizing the difference in the reaction activities of the two isocyanate groups.

[0011] As a preferred embodiment of the present invention, the functional monomer in the macromonomer of the terminal vinyl polyether is selected from one or more of 3-butene-1-ol, 4-pentene-1-ol, and 7-octene-1-ol.

[0012] The technical principle is as follows: The hydroxyl group in the functional monomer reacts with the -NCO on the side with high reaction activity in IPDI to obtain an intermediate. One end of the intermediate has a vinyl group, and the other end has a -NCO with low reaction activity. Subsequently, polyether polyol is added and continues to react with the -NCO with low activity to obtain a long-chain terminal vinyl polyether, and the long-chain terminal vinyl polyether is used for internal toughening of PVC.

[0013] The preparation method of the macromonomer of the terminal vinyl polyether specifically includes the following steps: S1. Add 4-pentene-1-ol to the reaction kettle, start the stirrer, slowly add IPDI and mix under stirring. The feeding ratio is 1:1. Introduce nitrogen to remove the air in the reaction kettle and create an anaerobic environment to prevent the reactants from being oxidized.

[0014] S2. Gradually raise the temperature to 50 - 60 °C and react at this temperature for 1 - 2 hours.

[0015] S3. After the reaction is complete, lower the reaction temperature to 40 - 50 °C, and then slowly add polyether polyol. Continue to stir to make the polyether polyol fully contact and react with the remaining -NCO in the system.

[0016] S4. Gradually raise the temperature to 70 - 80 °C, maintain this temperature and react for 2 - 4 hours to obtain the terminal vinyl polyether.

[0017] As a preferred embodiment of the present invention, in step S1, the feeding ratio of the functional monomer to the IPDI is 1:1; The technical principle is as follows: The functional monomer and IPDI are uniformly mixed at 70 - 100 °C in the presence of a tin catalyst. The hydroxyl group reacts with the highly reactive -NCO to form a product containing -NHCOO-. At the same time, one end of the molecular chain retains a carbon - carbon double bond, and the other end retains the less reactive -NCO. After reacting for 1 - 3 hours, polyether polyol is added to the reaction system and continues to react for 1 - 5 hours. The polyether polyol molecule contains multiple -OH groups, and these hydroxyl groups will continue to undergo an addition reaction with the remaining -NCO in the intermediate product formed in the previous reaction, obtaining a polyether macromonomer with vinyl groups at the ends. It is prepared by an addition reaction.

[0018] In the second aspect of the present invention, a preparation method of a modified PVC resin copolymerized with a vinyl - terminated polyether is provided. The modified PVC resin copolymerized with a vinyl - terminated polyether is the modified PVC resin described in the first aspect of the present invention, and specifically includes the following steps: S1. Add deionized water to the reaction kettle, heat up to 45 - 75 °C, add a dispersant, stir and dissolve it, with a rotation speed of 100 - 300 r / min and a stirring time of 10 - 50 min; S2. After the stirring ends, cool it, add an initiator and a vinyl - terminated polyether, and introduce vinyl chloride monomer in an inert atmosphere; S3. Stir at a rotation speed of 200 r / min, raise the temperature again to 50 - 55 °C and polymerize for 8 - 12 h, remove the unreacted vinyl chloride monomer, and obtain the modified PVC resin powder.

[0019] The technical principle is as follows: The modified PVC resin copolymerized with a vinyl - terminated polyether is prepared by suspension polymerization. The macromonomer of the above - mentioned vinyl - terminated polyether is mixed with each raw material to form a suspension, and polymerization is carried out at a temperature of 45 - 75 °C. After drying, the modified PVC resin powder copolymerized with a vinyl - terminated polyether is obtained.

[0020] As a preferred embodiment of the present invention, the modified PVC resin powder copolymerized with a vinyl - terminated polyether is mixed with an inorganic filler, a foaming agent, a stabilizer, and a lubricant according to a predetermined mass ratio and then extruded through a screw extruder at a temperature of 190 °C to obtain profiles, which can be used for co - extruded micro - foamed profiles for doors and windows.

[0021] Compared with the prior art, the technical solution of this application has the following beneficial effects: The modified PVC resin shown in the present invention is internally toughened by adding a long - chain vinyl - terminated polyether, which is combined with PVC by covalent bonds. At the same time, by designing the long - side - group structure, the distance between PVC molecular chains is increased and the intermolecular force is reduced, promoting the fluidity of the PVC chain, reducing the glass transition temperature of PVC, and improving the toughening ability of the modified PVC resin. Detailed implementation manners

[0022] The embodiments of the present invention will be described in detail below. The embodiments are exemplary and are intended to explain the present invention, and should not be construed as a limitation to the present invention.

[0023] It should be noted that these embodiments are only used to facilitate the understanding of those skilled in the art and should not be regarded as a limitation to the protection scope of the present invention. Unless otherwise specified, the reagents used in the embodiments can be obtained through commercial purchase. Example 1

[0024] A modified PVC resin copolymerized with vinyl-terminated polyether is prepared by the following method: According to the molar ratio of the feed materials 4-penten-1-ol: IPDI = 1:1, 20 kg of 4-penten-1-ol is weighed and added to the reaction kettle. The stirrer is started, and 51.6 kg of IPDI is slowly added under stirring. Before the reaction, nitrogen is introduced to remove the air in the reaction kettle to prevent the reactants from being oxidized. The stirring speed is set at 200 r / min, and the temperature is gradually raised to 50 - 60 °C, and the reaction is carried out at this temperature for 1 - 2 hours. After the reaction is complete, the reaction temperature is lowered to 40 - 50 °C, and then 92.88 kg of a difunctional polyether polyol with a molecular weight of 400 is slowly added. Subsequently, the stirring speed is increased to 400 r / min to allow the polyether diol to fully contact and react with the remaining isocyanate groups in the system, and the temperature is gradually raised to 70 - 80 °C, and the reaction is maintained at this temperature for 2 - 4 hours to obtain the vinyl-terminated polyether.

[0025] Subsequently, the vinyl-terminated polyether macromonomer prepared above is copolymerized with vinyl chloride monomer to obtain a modified PVC resin. The specific steps are as follows: 60 kg of deionized water is added to the reaction kettle, and the temperature is raised to 60 °C. 0.3 kg of dispersant PVA is added and stirred to dissolve at a rotation speed of 300 r / min for 15 min. After the stirring is completed, it is cooled, 0.02 kg of initiator IPP is added, and according to the mass ratio of the feed materials vinyl chloride monomer: vinyl-terminated polyether = 20:1, 2.0 kg of vinyl-terminated polyether is further added. Then, argon is introduced to displace the air in the kettle, and 40 kg of vinyl chloride monomer is introduced. The stirring is started at a rotation speed of 200 r / min, the polymerization temperature is 55 °C, and the polymerization time is 10 h. After the reaction is completed, the unreacted vinyl chloride monomer is removed, and after washing and drying, a PVC copolymer, that is, a modified PVC resin, is obtained. Example 2

[0026] A modified PVC resin copolymerized with vinyl-terminated polyether is prepared by the following method: According to the molar ratio of the feed materials 7-octen-1-ol:IPDI = 1:1, weigh 20 kg of 7-octen-1-ol and add it to the reaction kettle. Start the stirrer and slowly add 34.7 kg of IPDI under stirring. Before the reaction, introduce nitrogen to remove the air in the reaction kettle to prevent the reactants from being oxidized. Set the stirring speed to 200 r / min, gradually heat up to 50 - 60 °C, and react at this temperature for 1 - 2 hours. After the reaction is complete, lower the reaction temperature to 40 - 50 °C, and then slowly add 62.40 kg of polyether polyol with a difunctionality of 400. Subsequently, increase the stirring speed to 400 r / min to make the polyether diol fully contact and react with the remaining isocyanate groups in the system, and gradually heat up to 70 - 80 °C, and maintain this temperature for 2 - 4 hours to obtain the terminal vinyl polyether.

[0027] Subsequently, copolymerize the terminal vinyl polyether macromonomer prepared above with vinyl chloride monomer to obtain a modified PVC resin. The specific steps are as follows: Add 60 kg of deionized water to the reaction kettle, heat up to 60 °C, add 0.3 kg of dispersant PVA and start stirring to dissolve it. The rotation speed is 300 r / min, and the stirring time is 15 min. After the stirring is completed, cool down, add 0.02 kg of initiator IPP, and according to the mass ratio of the feed materials vinyl chloride monomer:terminal vinyl polyether = 20:1, continue to add 2.0 kg of terminal vinyl polyether, then displace the air in the kettle with argon, and introduce 40 kg of vinyl chloride monomer. Start stirring, the rotation speed is 200 r / min, the polymerization temperature is 55 °C, and the polymerization time is 10 h. After the reaction is completed, remove the unreacted vinyl chloride monomer, wash and dry to obtain a PVC copolymer, that is, the modified PVC resin. Example 3

[0028] A modified PVC resin copolymerized with terminal vinyl polyether is prepared by the following method: According to the molar ratio of the feed materials 4-penten-1-ol:IPDI = 1:1, weigh 20 kg of 4-penten-1-ol and add it to the reaction kettle. Start the stirrer and slowly add 51.6 kg of IPDI under stirring. Before the reaction, introduce nitrogen to remove the air in the reaction kettle to prevent the reactants from being oxidized. Set the stirring speed to 200 r / min, gradually heat up to 50 - 60 °C, and react at this temperature for 1 - 2 hours. After the reaction is complete, lower the reaction temperature to 40 - 50 °C, and then slowly add 232.20 kg of polyether polyol with a difunctionality of 1000. Subsequently, increase the stirring speed to 400 r / min to make the polyether diol fully contact and react with the remaining isocyanate groups in the system, and gradually heat up to 70 - 80 °C, and maintain this temperature for 2 - 4 hours to obtain the terminal vinyl polyether.

[0029] Subsequently, the prepared vinyl-terminated polyether macromonomer was copolymerized with vinyl chloride monomer to obtain a modified PVC resin. The specific steps are as follows: Add 60 kg of deionized water into the reaction kettle, heat up to 60 °C, add 0.3 kg of dispersant PVA and start stirring to dissolve it. The stirring speed is 300 r / min, and the stirring time is 15 min. After the stirring is completed, cool it down, add 0.02 kg of initiator IPP, and according to the feeding mass ratio of vinyl chloride monomer: vinyl-terminated polyether = 20:1, continue to add 2.0 kg of vinyl-terminated polyether, then purge the air in the kettle with argon, and introduce 40 kg of vinyl chloride monomer. Start stirring, the stirring speed is 200 r / min, the polymerization temperature is 55 °C, and the polymerization time is 10 h. After the reaction is completed, remove the unreacted vinyl chloride monomer, wash and dry to obtain a PVC copolymer, that is, the modified PVC resin. Example 4

[0030] A modified PVC resin copolymerized with vinyl-terminated polyether is prepared by the following method: According to the molar ratio of the feed of 4-penten-1-ol: IPDI = 1:1, weigh 20 kg of 4-penten-1-ol and add it to the reaction kettle. Start the stirrer and slowly add 51.6 kg of IPDI under stirring. Before the reaction, introduce nitrogen to remove the air in the reaction kettle to prevent the reactants from being oxidized. Set the stirring speed to 200 r / min, gradually heat up to 50 - 60 °C, and react at this temperature for 1 - 2 hours. After the reaction is complete, lower the reaction temperature to 40 - 50 °C, and then slowly add 464.40 kg of polyether diol with a difunctionality of 2000. Subsequently, increase the stirring speed to 400 r / min to make the polyether diol fully contact and react with the remaining isocyanate groups in the system, and gradually heat up to 70 - 80 °C and maintain this temperature for 2 - 4 hours to obtain the vinyl-terminated polyether.

[0031] Subsequently, the prepared vinyl-terminated polyether macromonomer was copolymerized with vinyl chloride monomer to obtain a modified PVC resin. The specific steps are as follows: Add 60 kg of deionized water into the reaction kettle, heat up to 60 °C, add 0.3 kg of dispersant PVA and start stirring to dissolve it. The stirring speed is 300 r / min, and the stirring time is 15 min. After the stirring is completed, cool it down, add 0.02 kg of initiator IPP, and according to the feeding mass ratio of vinyl chloride monomer: vinyl-terminated polyether = 20:1, continue to add 2.0 kg of vinyl-terminated polyether, then purge the air in the kettle with argon, and introduce 40 kg of vinyl chloride monomer. Start stirring, the stirring speed is 200 r / min, the polymerization temperature is 55 °C, and the polymerization time is 10 h. After the reaction is completed, remove the unreacted vinyl chloride monomer, wash and dry to obtain a PVC copolymer, that is, the modified PVC resin. Example 5

[0032] A modified PVC resin copolymerized with terminal vinyl polyether is prepared by the following method: According to the molar ratio of the feed materials 4-penten-1-ol:IPDI = 1:1, 20 kg of 4-penten-1-ol is weighed and added into the reaction kettle. The stirrer is started, and 51.6 kg of IPDI is slowly added under stirring. Before the reaction, nitrogen is introduced to remove the air in the reaction kettle to prevent the reactants from being oxidized. The stirring speed is set at 200 r / min, and the temperature is gradually raised to 50 - 60 °C, and the reaction is carried out at this temperature for 1 - 2 hours. After the reaction is complete, the reaction temperature is lowered to 40 - 50 °C, and then 696.61 kg of a trifunctional polyether polyol with a molecular weight of 3000 is slowly added. Subsequently, the stirring speed is increased to 400 r / min to make the polyether triol fully contact and react with the remaining isocyanate groups in the system, and the temperature is gradually raised to 70 - 80 °C, and the reaction is carried out at this temperature for 2 - 4 hours to obtain the terminal vinyl polyether.

[0033] Subsequently, the terminal vinyl polyether macromonomer prepared above is copolymerized with vinyl chloride monomer to obtain the modified PVC resin. The specific steps are as follows: 60 kg of deionized water is added into the reaction kettle, the temperature is raised to 60 °C, 0.3 kg of dispersant PVA is added and the stirring is started to dissolve, the rotation speed is 300 r / min, and the stirring time is 15 min. After the stirring is completed, it is cooled, 0.02 kg of initiator IPP is added, and according to the mass ratio of the feed materials vinyl chloride monomer:terminal vinyl polyether = 20:1, 2.0 kg of terminal vinyl polyether is continuously added, then argon is introduced to displace the air in the kettle, 40 kg of vinyl chloride monomer is introduced, the stirring is started, the rotation speed is 200 r / min, the polymerization temperature is 55 °C, and the polymerization time is 10 h. After the reaction is completed, the unreacted vinyl chloride monomer is removed, and after washing and drying, the PVC copolymer, that is, the modified PVC resin, is obtained. Example 6

[0034] A modified PVC resin copolymerized with terminal vinyl polyether is prepared by the following method: According to the molar ratio of the feed materials 4-penten-1-ol:IPDI = 1:1, 20 kg of 4-penten-1-ol is weighed and added into the reaction kettle. The stirrer is started, and 51.6 kg of IPDI is slowly added under stirring. Before the reaction, nitrogen is introduced to remove the air in the reaction kettle to prevent the reactants from being oxidized. The stirring speed is set at 200 r / min, and the temperature is gradually raised to 50 - 60 °C, and the reaction is carried out at this temperature for 1 - 2 hours. After the reaction is complete, the reaction temperature is lowered to 40 - 50 °C, and then 1161.01 kg of a trifunctional polyether polyol with a molecular weight of 5000 is slowly added. Subsequently, the stirring speed is increased to 400 r / min to make the polyether triol fully contact and react with the remaining isocyanate groups in the system, and the temperature is gradually raised to 70 - 80 °C, and the reaction is carried out at this temperature for 2 - 4 hours to obtain the terminal vinyl polyether.

[0035] Subsequently, the prepared vinyl-terminated polyether macromonomer was copolymerized with vinyl chloride monomer to obtain a modified PVC resin. The specific steps are as follows: Add 60 kg of deionized water into the reaction kettle, heat up to 60 °C, add 0.3 kg of dispersant PVA and start stirring to dissolve it. The rotation speed is 300 r / min and the stirring time is 15 min. After stirring, cool down, add 0.02 kg of initiator IPP, and according to the feeding mass ratio of vinyl chloride monomer: vinyl-terminated polyether = 20:1, continue to add 2.0 kg of vinyl-terminated polyether, then purge the air in the kettle with argon, and introduce 40 kg of vinyl chloride monomer. Start stirring, the rotation speed is 200 r / min, the polymerization temperature is 55 °C, and the polymerization time is 10 h. After the reaction, remove the unreacted vinyl chloride monomer, wash and dry to obtain a PVC copolymer, that is, the modified PVC resin. Example 7

[0036] A modified PVC resin copolymerized with vinyl-terminated polyether is prepared by the following method: According to the molar ratio of the feed materials 4-penten-1-ol: IPDI = 1:1, weigh 20 kg of 4-penten-1-ol and add it into the reaction kettle. Start the stirrer and slowly add 51.6 kg of IPDI under stirring. Before the reaction, introduce nitrogen to remove the air in the reaction kettle to prevent the reactants from being oxidized. Set the stirring speed to 200 r / min, gradually heat up to 50 - 60 °C, and react at this temperature for 1 - 2 hours. After the reaction is complete, lower the reaction temperature to 40 - 50 °C, and then slowly add 92.88 kg of polyether polyol with a difunctionality of 400. Subsequently, increase the stirring speed to 400 r / min to make the polyether diol fully contact and react with the remaining isocyanate groups in the system, and gradually heat up to 70 - 80 °C and maintain this temperature for 2 - 4 hours to obtain the vinyl-terminated polyether.

[0037] Subsequently, the prepared vinyl-terminated polyether macromonomer was copolymerized with vinyl chloride monomer to obtain a modified PVC resin. The specific steps are as follows: Add 60 kg of deionized water into the reaction kettle, heat up to 60 °C, add 0.3 kg of dispersant PVA and start stirring to dissolve it. The rotation speed is 300 r / min and the stirring time is 15 min. After stirring, cool down, add 0.02 kg of initiator IPP, and according to the feeding mass ratio of vinyl chloride monomer: vinyl-terminated polyether = 100:7, continue to add 2.8 kg of vinyl-terminated polyether, then purge the air in the kettle with argon, and introduce 40 kg of vinyl chloride monomer. Start stirring, the rotation speed is 200 r / min, the polymerization temperature is 55 °C, and the polymerization time is 10 h. After the reaction, remove the unreacted vinyl chloride monomer, wash and dry to obtain a PVC copolymer, that is, the modified PVC resin.

[0038] Comparative Example 1: The comparative sample was prepared by the following method, including: Add 60 kg of deionized water into the reaction kettle, heat up to 60 °C, add 0.3 kg of dispersant PVA and start stirring to dissolve. The rotation speed is 300 r / min, and the stirring time is 15 min. After the stirring is completed, cool down, add 0.02 kg of initiator IPP, then introduce argon to displace the air in the kettle, and introduce 40 kg of vinyl chloride monomer. Start stirring, the rotation speed is 200 r / min, the polymerization temperature is 55 °C, and the polymerization time is 10 h. After the reaction is completed, remove the unreacted vinyl chloride monomer, wash and dry to obtain the PVC polymer.

[0039] The above examples and comparative examples all adopt the same extrusion molding process. Add 100 kg of PVC resin, 50 kg of calcium carbonate, 5 kg of calcium-zinc stabilizer, 2 kg of AC foaming agent, 1 kg of lubricant PE wax and other additives into a high-speed mixer for mixing, and perform twin-screw extrusion at about 190 °C to obtain PVC micro-foamed products.

[0040] The PVC micro-foamed products obtained in Examples 1-7 and Comparative Example 1 were tested for elongation at break, and the test results are shown in Table 1.

[0041] Table 1 Elongation at break Elongation at break / % Example 1 40.9 Example 2 38.9 Example 3 63.8 Example 4 69.9 Example 5 75.6 Example 6 79.2 Example 7 57.5 Comparative Example 1 26.4 Combined with the results given in the above Examples 1-7, it can be seen that the elongation at break of the modified PVC resin prepared by the present invention through copolymerization of terminal vinyl polyether is higher than that of Comparative Example 1 (Comparative Example 1 does not contain terminal vinyl polyether macromonomer). The carbon chain length of the functional monomer used in Example 2 is longer than that of Example 1, but the increase in the carbon chain length of the functional monomer used has little effect on the elongation at break; in Examples 1, 3, 4, 5, and 6, as the molecular weight of the polyether polyol increases, the elongation at break gradually increases, indicating that the copolymerization of the terminal vinyl polyether macromonomer and the vinyl chloride monomer realizes the internal toughening of PVC, weakens the sliding resistance between PVC molecules, and improves the flexibility and ductility of PVC; the elongation at break of Example 7 is higher than that of Example 1, indicating that the increase in the amount of terminal vinyl polyether contributes to its copolymerization with the vinyl chloride monomer and improves the internal toughening effect of PVC. The modified PVC resin has more excellent fracture toughness, is suitable for making steel-plastic co-extruded micro-foamed profiles for doors and windows, can have a higher calcium powder filling content, and reduces costs.

[0042] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

[0043] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A modified PVC resin copolymerized with terminal vinyl polyether, characterized in that It is prepared from raw materials including the following weights: 30 - 40 parts by weight of vinyl chloride monomer, 1.5 - 3.0 parts by weight of terminal vinyl polyether, 0.01 - 0.02 parts by weight of initiator, 0.2 - 0.4 parts by weight of dispersant, 50 - 70 parts by weight of dispersion medium.

2. The modified PVC resin obtained by copolymerizing terminal vinyl polyether according to claim 1, characterized in that, The macromonomer of the terminal vinyl polyether includes polyether polyol, isocyanate and functional monomer.

3. The modified PVC resin obtained by copolymerizing an end vinyl polyether according to claim 2, characterized in that, The polyether polyol of the macromonomer of the terminal vinyl polyether has a molecular weight of 400 - 5000 g / mol and a functionality of one or more of bifunctionality or trifunctionality.

4. The modified PVC resin obtained by copolymerizing a vinyl-terminated polyether according to claim 2, characterized in that, The isocyanate of the macromonomer of the terminal vinyl polyether is selected from isophorone diisocyanate (IPDI).

5. The modified PVC resin obtained by copolymerizing a vinyl-terminated polyether according to claim 2, characterized in that, One end of the functional monomer of the macromonomer of the terminal vinyl polyether contains a vinyl group, the other end contains a hydroxyl group, and the middle is a carbon chain.

6. The modified PVC resin obtained by copolymerizing the terminal vinyl polyether according to claim 2, characterized in that, The functional monomer of the macromonomer of the terminal vinyl polyether is selected from one or more of 3 - butene - 1 - ol, 4 - pentene - 1 - ol, 7 - octene - 1 - ol.

7. The modified PVC resin copolymerized with terminal vinyl polyether according to any one of claims 2-6, characterized in that, The preparation method of the macromonomer of the terminal vinyl polyether includes the following steps: S1. Add 4 - pentene - 1 - ol to the reaction kettle, start the stirrer, slowly add IPDI and mix under stirring, with a feed ratio of 1:1, introduce nitrogen to remove the air in the reaction kettle, create an anaerobic environment, and prevent the reactants from being oxidized; S2. Gradually raise the temperature to 50 - 60 °C and react at this temperature for 1 - 2 hours; S3. After the reaction is complete, lower the reaction temperature to 40 - 50 °C, then slowly add polyether polyol; continue stirring to make the polyether polyol fully contact and react with the remaining -NCO in the system; S4. Gradually raise the temperature to 70 - 80 °C, maintain this temperature and react for 2 - 4 hours to obtain the terminal vinyl polyether.

8. The modified PVC resin obtained by copolymerizing vinyl-terminated polyether according to claim 1, characterized in that, The initiator is selected from one or more of diisopropyl peroxydicarbonate (IPP), benzoyl peroxide, 2,2'-azobis(2 - methylbutyronitrile), 2,2'-azobis(isobutyronitrile), ammonium persulfate; the dispersant is one of polyvinyl alcohol (PVA) or sodium dodecylbenzenesulfonate; the dispersion medium is deionized water.

9. The preparation method of the modified PVC resin copolymerized with terminal vinyl polyether according to any one of claims 1-8, characterized in that, It includes the following steps: S1. Add deionized water to the reaction kettle, raise the temperature to 45 - 75 °C, add the dispersant, stir and dissolve, with a rotation speed of 100 - 300 r / min and a stirring time of 10 - 50 min; S2. After stirring, cool, add the initiator and terminal vinyl polyether, and introduce vinyl chloride monomer in an inert atmosphere; S3. Stir at a rotation speed of 200 r / min, raise the temperature again to 50 - 55 °C and polymerize for 8 - 12 h, remove the unreacted vinyl chloride monomer to obtain the modified PVC resin powder.

10. Use of the modified PVC resin copolymerized with terminal vinyl polyether according to claim 9, characterized in that, Based on the modified PVC resin, add inorganic filler, foaming agent, stabilizer, lubricant and extrude through a screw extruder to obtain profiles, which can be used for co - extruded micro - foamed profiles for doors and windows.