EASY-TO-PROCESS, OPAQUE AND HIGH-IMPACT METHYL METHACRYLATE-BUTADIENE-STYRENE POLYMER FOR POLYVINYL CHLORIDE AND PREPARATION METHOD THEREOF

Abstract

The present invention discloses an easy-to-process, opaque and high-impact methyl methacrylate-butadiene-styrene (MBS) polymer for polyvinyl chloride (PVC) and a preparation method thereof, and relates to the technical field of preparation of PVC additives. The easy-to-process, opaque and high-impact MBS for PVC has a core-kernel-shell (three-layer) structure, and includes the following components by mass: 1-20% of core, 70-85% of kernel and 5-20% of shell. The core is a semi-hard, lightly crosslinked copolymer of a styrene (St) monomer and an acrylate monomer. The kernel is a soft, lightly crosslinked butadiene (BD)-St polymer with a low glass transition temperature. The shell is a copolymer of St, butyl acrylate and methyl methacrylate (MMA) with a high glass transition temperature. The present invention solves the problems of low impact strength and poor processing fluidity of the existing MBS for opaque PVC products.

Claims

1. An easy-to-process, opaque and high-impact methyl methacrylate-butadiene-styrene (MBS) polymer for polyvinyl chloride (PVC), having a core-kernel-shell (three-layer) structure, wherein the MBS comprises the following components by mass: 1-20% of core, 70-85% of kernel and 5-20% of shell; the core is a semi-hard, lightly crosslinked copolymer of a styrene (St) monomer and an acrylate monomer; the ratio of the St monomer to the acrylate monomer is 95:5 to 5:95; the St monomer comprises St or methylstyrene; the acrylate monomer comprises one or more of methyl acrylate, ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate; the kernel is a soft, lightly crosslinked butadiene (BD)-St polymer with a low glass transition temperature, and the ratio of the BD to the St is 100:0 to 80:20; the shell is a copolymer of St, butyl acrylate and methyl methacrylate (MMA) with a high glass transition temperature; the St, the butyl acrylate and the MMA account for 0.2-5%, 0.2-2% and 13-20% by mass, respectively.

2. The easy-to-process, opaque and high-impact MBS for PVC according to claim 1, wherein the core accounts for 1-15%.

3. The easy-to-process, opaque and high-impact MBS for PVC according to claim 1, wherein the core accounts for 1-12%.

4. The easy-to-process, opaque and high-impact MBS for PVC according to claim 2 or 3, wherein the ratio of the St monomer to the acrylate monomer in the core is 90:10 to 10:90.

5. The easy-to-process, opaque and high-impact MBS for PVC according to claim 2 or 3, wherein the ratio of the St monomer to the acrylate monomer in the core is 85:15 to 15:85.

6. The easy-to-process, opaque and high-impact MBS for PVC according to claim 4, wherein the kernel accounts for 75-85%.

7. The easy-to-process, opaque and high-impact MBS for PVC according to claim 6, wherein the ratio of the BD to the St in the kernel is 100:0 to 85:15.

8. The easy-to-process, opaque and high-impact MBS for PVC according to claim 6, wherein the ratio of the BD to the St in the kernel is 100:0 to 90:10.

9. The easy-to-process, opaque and high-impact MBS for PVC according to claim 6, wherein the ratio of the BD to the St in the kernel is 100:0 to 95:5.

10. The easy-to-process, opaque and high-impact MBS for PVC according to claim 7, 8 or 9, wherein the shell accounts for 7-20%.

11. The easy-to-process, opaque and high-impact MBS for PVC according to claim 7, 8 or 9, wherein the shell accounts for 9-19%.

12. A method for preparing the easy-to-process, opaque and high-impact MBS for PVC according to claim 1, specifically comprising the following steps: (1) adding water, an emulsifier, an inorganic salt, a molecular weight regulator, a copolymer of a St monomer and an acrylate monomer, a crosslinking agent and an initiator to a reactor according to a formulated amount; closing a lid of the reactor, and heating to a reaction temperature to carry out a reaction until the reaction is completed; or adding an emulsion that has been reacted at the formulated amount into a separate MBS reactor to carry out the reaction to form a core seed; (2) adding water, an emulsifier, an inorganic salt solution, a molecular weight regulator, a crosslinking agent and an initiator to a high pressure reactor; closing a lid of the reactor and tightening a bolt; injecting BD or a BD-St copolymer into the reactor; (3) heating to 70° C. until the reaction is completed; (4) adding a mixture of emulsifier, outer St monomer, butyl acrylate and MMA to the reactor; continuing the reaction for 1-3 h until the reaction is completed; and (5) discharging a reaction product; coagulating a latex by a coagulation method; then centrifuging by a centrifuge, drying by a bubbling fluidized bed (BFB), sieving, and packing to obtain a finished product.

Description

DETAILED DESCRIPTION

[0033] In order to further explain the beneficial effects of the present invention, a large number of tests have been performed. It should be noted that the tests of the present invention are intended to illustrate the beneficial technical effects of the present invention, and are not limited to the scope of the present invention.

EXAMPLE 1

[0034] (1) Add water, an emulsifier, an inorganic salt, a molecular weight regulator, a copolymer of a styrene (St) monomer and a butyl acrylate monomer (95:5), a crosslinking agent and an initiator to a reactor according to a formulated amount; close a lid of the reactor, and heat to a reaction temperature to carry out a reaction until the reaction is completed; or add an emulsion that has been reacted at the formulated amount into a separate MBS reactor to carry out the reaction to form a core seed, the core accounting for 10%.

[0035] (2) Add water, an emulsifier, an inorganic salt solution, a 10% core seed, a molecular weight regulator, a crosslinking agent and an initiator to a high pressure reactor; close a lid of the reactor and tighten a bolt; inject butadiene (BD) and St into the reactor, where the ratio of the BD to the St is 95:5, and an intermediate layer accounts for 75%.

[0036] (3) Heat to 70° C. until the reaction is completed.

[0037] (4) Add a mixture of emulsifier, outer St monomer, butyl acrylate and methyl methacrylate (MMA) which account for 2%, 2% and 11% respectively to the reactor; continue the reaction for 1-3 h until the reaction is completed.

[0038] (5) Discharge a reaction product; coagulate a latex by a coagulation method; then centrifuge by a centrifuge, dry by a bubbling fluidized bed (BFB), sieve, and pack to obtain a finished product.

EXAMPLE 2

[0039] The ratio of the St monomer to the butyl acrylate monomer in the core in step (1) of Example 1 was changed as 75:25, and the rest were the same as in Example 1.

EXAMPLE 3

[0040] The ratio of the St monomer to the butyl acrylate monomer in the core in step (1) of Example 1 was changed as 50:50, and the rest were the same as in Example 1.

EXAMPLE 4

[0041] The ratio of the St monomer to the butyl acrylate monomer in the core in step (1) of Example 1 was changed as 25:75, and the rest were the same as in Example 1.

EXAMPLE 5

[0042] The ratio of the St monomer to the butyl acrylate monomer in the core in step (1) of Example 1 was changed as 5:95, and the rest were the same as in Example 1.

EXAMPLE 6

[0043] The ratio of the BD to the St in the intermediate layer in step (2) of Example 1 was changed as 80:20, and the rest were the same as in Example 1.

EXAMPLE 7

[0044] The ratio of the BD to the St in the intermediate layer in step (2) of Example 1 was changed as 90:10, and the rest were the same as in Example 1.

EXAMPLE 8

[0045] The intermediate layer in step (2) of Example 1 was changed to pure BD, and the remaining were the same as in Example 1.

EXAMPLE 9

[0046] The proportion of the core in step (1) of Example 1 was changed to 3%, and the proportion of the intermediate layer in step (2) was changed to 82%; the rest were the same as in Example 1.

EXAMPLE 10

[0047] The proportion of the core in step (1) of Example 2 was changed to 3%, and the proportion of the intermediate layer in step (2) was changed to 82%; the rest were the same as in Example 2.

EXAMPLE 11

[0048] The proportion of the core in step (1) of Example 3 was changed to 3%, and the proportion of the intermediate layer in step (2) was changed to 82%; the rest were the same as in Example 3.

EXAMPLE 12

[0049] The proportion of the core in step (1) of Example 4 was changed to 3%, and the proportion of the intermediate layer in step (2) was changed to 82%, and the rest were the same as in Example 4.

EXAMPLE 13

[0050] The proportion of the core in step (1) of Example 5 was changed to 3%, and the proportion of the intermediate layer in step (2) was changed to 82%, and the rest were the same as in Example 5.

EXAMPLE 14

[0051] The proportion of the core in step (1) of Example 1 was changed to 15%, and the proportion of the intermediate layer in step (2) was changed to 70%, and the rest were the same as in Example 1.

EXAMPLE 15

[0052] The proportion of the core in step (1) of Example 2 was changed to 15%, and the proportion of the intermediate layer in step (2) was changed to 70%; the rest were the same as in Example 2.

COMPARATIVE EXAMPLE 1

[0053] The core in Example 1 was replaced with an intermediate layer, and the rest were the same as in Example 1.

COMPARATIVE EXAMPLE 2

[0054] The core in Example 2 was replaced with an intermediate layer, and the rest were the same as in Example 2.

COMPARATIVE EXAMPLE 3

[0055] The core in Example 3 was replaced with an intermediate layer, and the rest were the same as in Example 3.

COMPARATIVE EXAMPLE 4

[0056] The core in Example 4 was replaced with an intermediate layer, and the rest were the same as in Example 4.

COMPARATIVE EXAMPLE 5

[0057] The core in Example 5 was replaced with an intermediate layer, and the rest were the same as in Example 5.

COMPARATIVE EXAMPLE 6

[0058] The core in Example 6 was replaced with an intermediate layer, and the rest were the same as in Example 6.

COMPARATIVE EXAMPLE 7

[0059] The core in Example 7 was replaced with an intermediate layer, and the rest were the same as in Example 7.

COMPARATIVE EXAMPLE 8

[0060] The core in Example 8 was replaced with an intermediate layer, and the rest were the same as in Example 8.

COMPARATIVE EXAMPLE 9

[0061] The ratio of the St to the butyl acrylate in the core in Example 1 was changed as 100:0, and the rest were the same as in Example 1.

COMPARATIVE EXAMPLE 10

[0062] The ratio of the St to the butyl acrylate in the core in Example 1 was changed as 0:100, and the rest were the same as in Example 1.

[0063] Table 1 provides a result of performance comparison of the easy-to-process, opaque and high-impact MBS for PVC obtained by the examples and the products obtained by the comparative examples of the present invention.

TABLE-US-00001 TABLE 1 Performance comparison of products obtained by examples and comparative examples Brittleness of Processing downstream Impact Instance fluidity products resistance Examples Example 1 ⊚⊚⊚⊚⊚ •••• 17.5 Example 2 ⊚⊚⊚⊚⊚ ••••• 17.8 Example 3 ⊚⊚⊚⊚⊚ ••••• 18.4 Example 4 ⊚⊚⊚⊚⊚ ••••• 18.0 Example 5 ⊚⊚⊚⊚⊚ ••••• 17.1 Example 6 ⊚⊚⊚⊚⊚ ••••• 15.1 Example 7 ⊚⊚⊚⊚⊚ ••••• 16.9 Example 8 ⊚⊚⊚⊚⊚ ••••• 17.1 Example 9 ⊚⊚⊚ ••••• 17.5 Example 10 ⊚⊚⊚ ••••• 15.2 Example 11 ⊚⊚⊚ ••••• 15.8 Example 12 ⊚⊚⊚ ••••• 16.9 Example 13 ⊚⊚⊚ ••••• 15.9 Example 14 ⊚⊚⊚⊚⊚ ••••• 15.2 Example 15 ⊚⊚⊚⊚⊚ ••••• 15.8 Comparative Comparative ⊚⊚ ••••• 15.1 Examples Example 1 Comparative ⊚⊚ ••••• 14.9 Example 2 Comparative ⊚⊚ ••••• 14.6 Example 3 Comparative ⊚⊚ ••••• 14.2 Example 4 Comparative ⊚⊚ ••••• 13.9 Example 5 Comparative ⊚⊚ ••••• 13.2 Example 6 Comparative ⊚⊚ ••••• 13.5 Example 7 Comparative ⊚⊚ ••••• 14.1 Example 8 Comparative ⊚⊚ •• 16.3 Example 9 Comparative ⊚⊚ ••••• 14.2 Example 10

[0064] Remarks:

[0065] 1. (1) Processing Fluidity

[0066] Low ⊚, ⊚⊚, ⊚⊚⊚, ⊚⊚⊚⊚, ⊚⊚⊚⊚⊚ high;

[0067] (2) Brittleness of Downstream Products: Higher Brittleness Leads to Poorer Performance

[0068] High .circle-solid., .circle-solid..circle-solid., .circle-solid..circle-solid..circle-solid., .circle-solid..circle-solid..circle-solid..circle-solid., .circle-solid..circle-solid..circle-solid..circle-solid..circle-solid. low;

[0069] 2. The formula used to improve the impact strength in the table includes 100 parts of PVC, 1.2 parts of organotin, 12 parts of light calcium carbonate, 0.6 parts of DL-74 (polyethylene wax), 0.6 parts of DL-60 (pentaerythritol stearate), 0.9 parts of calcium stearate, 5 parts of titanium dioxide and 8 parts of MBS.

[0070] The present invention is applicable to opaque MBS, transparent MBS MBS used for engineering plastics, and impact-resistant acrylic copolymer (ACR).

[0071] The above described are merely preferred examples of the present invention and are not intended to limit the present invention in any form. Any simple variations, material changes and equivalent transformations and modifications made to the above examples based on the technical essence of the present invention without departing from the technical solution of the present invention should fall within the scope of the technical solution of the present invention.

[0072] The above description of the examples is intended to help understand the method and core idea of the present invention. It should be noted that, several improvements and modifications may be made by persons of ordinary skill in the art without departing from the principle of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention. Various modifications to these examples are readily apparent to persons skilled in the art, and the generic principles defined herein may be practiced in other examples without departing from the spirit or scope of the invention. Thus, the present invention is not limited to the examples shown herein but falls within the widest scope consistent with the principles and novel features disclosed herein.