阅读说明：本技术 生产聚合物掺混物的方法 (Method for producing polymer blends ) 是由 J·P·A·马腾斯 R·J·P·施普尔 于 2018-05-28 设计创作，主要内容包括：本发明涉及生产热塑性淀粉和聚烯烃的掺混物的方法,其中应用第一挤出机和第二挤出机,所述第一挤出机和第二挤出机均包括含第一区、第二区、第三区和第四区的连续区,所述方法包括如下步骤：1a)在第一挤出机的第一区中引入聚烯烃和相容剂,1b)在第一挤出机的第二区中熔融混合所述聚烯烃和相容剂,1c)在第一挤出机的第三区中向步骤1b)的混合物中加入热塑性淀粉,和1d)在第一挤出机的第四区中熔融混合步骤1c)的混合物以得到掺混物,其中通过包括如下步骤的方法在第二挤出机中生产热塑性淀粉：2a)在第二挤出机的第一区中引入淀粉,2b)在第二挤出机的第二区中向步骤2a)的混合物中加入增塑剂以获得热塑性淀粉,2c)在第二挤出机的第三区中使步骤2b)的热塑性淀粉脱气,和2d)在第二挤出机的第四区中使步骤2c)的脱气后热塑性淀粉加压以被移入第一挤出机的第三区。(The present invention relates to a process for producing a blend of thermoplastic starch and polyolefin, wherein a first extruder and a second extruder are used, each comprising a continuous zone comprising a first zone, a second zone, a third zone and a fourth zone, the process comprising the steps of: 1a) introducing a polyolefin and a compatibilising agent in a first zone of a first extruder, 1b) melt mixing the polyolefin and compatibilising agent in a second zone of the first extruder, 1c) adding thermoplastic starch to the mixture of step 1b) in a third zone of the first extruder, and 1d) melt mixing the mixture of step 1c) in a fourth zone of the first extruder to obtain a blend, wherein the thermoplastic starch is produced in the second extruder by a method comprising the steps of: 2a) introducing starch in a first zone of a second extruder, 2b) adding a plasticizer to the mixture of step 2a) in a second zone of the second extruder to obtain thermoplastic starch, 2c) degassing the thermoplastic starch of step 2b) in a third zone of the second extruder, and 2d) pressurizing the degassed thermoplastic starch of step 2c) in a fourth zone of the second extruder to be moved into the third zone of the first extruder.)

1. A process for producing a blend of thermoplastic starch and polyolefin wherein a first extruder and a second extruder are employed, each of said first and second extruders comprising a continuous zone comprising a first zone, a second zone, a third zone and a fourth zone, said process comprising the steps of:

1a) introducing a polyolefin and a compatibilizer in a first zone of a first extruder,

1b) melt mixing the polyolefin and the compatibilizer in a second zone of the first extruder,

1c) adding thermoplastic starch to the mixture of step 1b) in a third zone of the first extruder, and

1d) melt mixing the mixture of step 1c) in a fourth zone of the first extruder to obtain a blend,

wherein the thermoplastic starch is produced in a second extruder by a process comprising the steps of:

2a) starch is introduced in the first zone of the second extruder,

2b) adding a plasticizer to the mixture of step 2a) in a second zone of a second extruder to obtain thermoplastic starch,

2c) degassing the thermoplastic starch of step 2b) in a third zone of the second extruder, and

2d) pressurizing the degassed thermoplastic starch of step 2c) in a fourth zone of the second extruder to be moved into a third zone of the first extruder.

2. The process of claim 1 wherein the polyolefin is present in an amount of 10 to 70 wt%, the compatibilizer is present in an amount of 3 to 30 wt% and/or the thermoplastic starch is present in an amount of 10 to 70 wt% of the blend.

3. The process of any of the preceding claims wherein the polyolefin is selected from the group consisting of propylene homopolymers, ethylene propylene copolymers, polyethylenes such as high density polyethylene, medium density polyethylene, low density polyethylene, linear low density polyethylene, and mixtures of at least two of the foregoing polyolefins.

4. The method of any of the preceding claims, wherein the compatibilizer is selected from the group consisting of ethylene-acrylic acid copolymers, ethylene-vinyl acetate copolymers, polyolefins having at least 1 weight percent maleic anhydride grafted thereon, ethylene-vinyl alcohol copolymers, block saponified polyvinyl acetate, random terpolymers of ethylene, butyl acrylate, and maleic anhydride, random partially hydrolyzed and saponified polyvinyl acetate, and mixtures of at least two of these compatibilizers.

5. The method according to any of the preceding claims, wherein the amount of starch is about 30-90 wt%, such as 35-80 wt%, 35-70 wt%, 35-60 wt% or 40-50 wt%, relative to the total weight of starch and plasticizer.

6. The method of any preceding claim, wherein the plasticizer is a glycerol and/or sorbitol plasticizer.

7. The process according to any of the preceding claims, wherein step 2c) is carried out at a temperature of 110-140 ℃.

8. The process of any of the preceding claims, wherein the first extruder and the second extruder are both twin screw extruders.

9. A process for producing a biaxially stretched film comprising a process for producing a blend according to any of claims 1 to 8 and stretching said blend at elevated temperature in the machine and transverse directions.

10. A blend of thermoplastic starch and a polyolefin obtained or obtainable by the process of any one of claims 1 to 8.

11. A biaxially stretched film obtained or obtainable by the process of claim 9.

12. A biaxially stretched film obtained or obtainable by the process of claim 9, wherein the film has a transparency of at least 60%, preferably 70%, more preferably 75%.

13. A multilayer film comprising the biaxially stretched film of claims 11-12 and a polymer film provided on each side of the biaxially stretched film.

14. A multilayer film comprising a biaxially stretched film according to claims 11 to 12 and a polymer film provided on each side of the biaxially stretched film, wherein the film has a transparency of at least 60%, preferably 70%, more preferably 75%.

15. Use of the film according to claims 11-14 for food packaging.

Examples	Degree of transparency%
		1	77.0
2	82.9
		3	88.0
4	81.1
		5	80.4
6	76.7
		A	29.6
B	24.9
		C	24.0

As is clear from Table 2, inventive examples 1-6 exhibited higher transparency than comparative examples A-C.