REPROCESSED MATERIAL OF RECYCLED POLYVINYL BUTYRAL AND METHOD FOR PRODUCING THE SAME, HOT MELT ADHESIVE AND COMPOSITE MATERIAL FILM

Abstract

Provided are a reprocessed material of recycled polyvinyl butyral and the method for producing the same. The method comprises steps (A) and (B); step (A): heating a first mixture comprising recycled polyvinyl butyral and an antiblocking agent; and step (B): adding a free radical initiator into the first mixture to undergo a reaction to obtain the reprocessed material of recycled polyvinyl butyral; wherein the free radical initiator comprises an azo compound, an organic peroxide or a combination thereof; the reprocessed material of recycled polyvinyl butyral has a MI of greater than 7 g/10 min at 190° C. and under 2.16 kg of load. The reprocessed material of recycled polyvinyl butyral has excellent reprocessability, so it is applicable to make a hot adhesive and a composite material film.

Claims

1. A method of producing a reprocessed material of recycled polyvinyl butyral, comprising steps of: step (A): heating a first mixture, which comprises recycled polyvinyl butyral and an antiblocking agent; and step (B): adding a free radical initiator into the first mixture to undergo a reaction, so as to obtain the reprocessed material of recycled polyvinyl butyral; wherein the free radical initiator comprises an azo compound, an organic peroxide or a combination thereof; the organic peroxide is selected from a group consisting of: 2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane, dilauroyl peroxide, benzoyl peroxide and any combination thereof; wherein the reprocessed material of recycled polyvinyl butyral has a melt flow index (MI) of greater than 7 g/10 min at a temperature of 190° C. and under 2.16 kg of load. 2. The method of claim 1, wherein a heating temperature in the step (A) ranges from 50° C. to 120° C.

2. The method of claim 1, wherein a heating temperature in the step (A) ranges from 50° C. to 120° C.

3. The method of claim 1, wherein a half-life of the free radical initiator in the step (B) is 0.1 hour at a temperature from 80° C. to 130° C.

4. The method of claim 1, wherein the step (B) comprises: step (b1): adding the free radical initiator into the first mixture to undergo the reaction to obtain a first intermediate; and step (b2): mixing an additive with the first intermediate, so as to obtain the reprocessed material of recycled polyvinyl butyral.

5. The method of claim 4, wherein a reaction temperature in the step (b1) ranges from 60° C. to 140° C.

6. The method of claim 4, wherein the additive comprises an ultraviolet absorber, an antioxidant or a combination thereof.

7. The method of claim 6, wherein the additive is in an amount from 0.1 wt% to 4.5 wt% based on a total dry weight of the reprocessed material of recycled polyvinyl butyral.

8. The method of claim 1, wherein the antiblocking agent is in an amount from 0.05 parts by weight to 5.0 parts by weight, based on 100 parts by weight of the recycled polyvinyl butyral in the first mixture.

9. The method of claim 1, wherein the azo compound comprises 2,2′-azobis(2-methylpropionitrile), 2,2′-azobis(2-methylbutyronitrile), 1,1′-azobis(cyclohexane-1-carbonitrile) or any combination thereof.

10. The method of claim 9, wherein the azo compound is in an amount from 0.1 parts by weight to 8.0 parts by weight, based on 100 parts by weight of the recycled polyvinyl butyral in the first mixture.

11. The method of claim 1, wherein the free radical initiator is a combination of 2,2′-azobis(2-methylpropionitrile) and dilauroyl peroxide, a combination of 2,2′-azobis(2-methylbutyronitrile) and benzoyl peroxide, or a combination of 2,2′-azobis(2-methylpropionitrile) and benzoyl peroxide.

12. The method of claim 1, wherein the organic peroxide is in an amount from 0.01 parts by weight to 2.5 parts by weight, based on 100 parts by weight of the recycled polyvinyl butyral in the first mixture.

13. A reprocessed material of recycled polyvinyl butyral produced by the method of claim 1; wherein the reprocessed material of recycled polyvinyl butyral has a MI of greater than 7 g/10 min at a temperature of 190° C. and under 2.16 kg of load.

14. The reprocessed material of recycled polyvinyl butyral of claim 13, wherein the reprocessed material of recycled polyvinyl butyral has the MI of greater than or equal to 10 g/10 min and smaller than or equal to 35 g/10 min at a temperature of 190° C. and under 2.16 kg of load.

15. The reprocessed material of recycled polyvinyl butyral of claim 13, wherein the reprocessed material of recycled polyvinyl butyral has a shape of pellet or thin-film.

16. A hot melt adhesive comprising the reprocessed material of recycled polyvinyl butyral of claim 13.

17. The hot melt adhesive of claim 16, wherein the hot melt adhesive further comprises a thermoplastic polyurethane with a low-melting-point; and the thermoplastic polyurethane with a low-melting-point has a flow beginning temperature of larger than or equal to 80° C. and smaller than or equal to 120° C.

18. The hot melt adhesive of claim 17, wherein the thermoplastic polyurethane with a low-melting-point is a recycled thermoplastic polyurethane.

19. A composite material film comprising a thermoplastic polyurethane with a high-melting-point and the reprocessed material of recycled polyvinyl butyral of claim 13; wherein the thermoplastic polyurethane with a high-melting-point has a flow beginning temperature of larger than 120° C. and smaller than or equal to 170° C.

20. The composite material film of claim 19, wherein the thermoplastic polyurethane with a high-melting-point is a recycled thermoplastic polyurethane.

Description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0043] Hereinafter, one skilled in the arts can easily realize the advantages and effects of the present invention from the following examples and reference examples. It should be understood that the descriptions proposed herein are just preferable examples only for the purpose of illustrations, not intended to limit the scope of the invention. Various modifications and variations could be made in order to practice or apply the present invention without departing from the spirit and scope of the invention.

Raw Materials

[0044] 1. rPVB-1: a PIR PVB purchased from Protrade Asia Limited; the PIR PVB is obtained by recycling scraps generated from the PVB products; [0045] 2. rPVB-2: a PCR PVB purchased from Protrade Asia Limited; [0046] 3. Antiblocking agent: zinc stearate; [0047] 4. Azo compound I: AIBN purchased from Nouryon Co., Ltd.; [0048] 5. Azo compound II: AMBN purchased from Nouryon Co., Ltd.; [0049] 6. Azo compound III: ACCN purchased from Nouryon Co., Ltd.; [0050] 7. Organic peroxide a: LPO purchased from Nouryon Co., Ltd.; [0051] 8.Organic peroxide b: BPO purchased from Taiwan Shirakawa Chemical Industry Co., Ltd; [0052] 9. UV absorber: Lowilite 20 purchased from Ming Ching Trading co., Ltd.; [0053] 10. Antioxidant: ANOX 1315 purchased from Ming Ching Trading co., Ltd.; [0054] 11. TPU-i: 80 AU having a Tfb of 110° C. purchased from Eastern Resins Industrial Co. Ltd.; [0055] 12. TPU-ii: 85 AN having a Tfb of 113° C. purchased from Eastern Resins Industrial Co. Ltd.; [0056] 13. TPU-iii: 85 UL having a Tfb of 106° C. purchased from Eastern Resins Industrial Co. Ltd.; [0057] 14. TPU-iv: 85A DP2 having a Tfb of 125° C. purchased from Jah Yih Enterprise Co. Ltd.; [0058] 15. TPU-v: RS1-90A DP2 having a Tfb of 138° C. purchased from Jah Yih Enterprise Co. Ltd.; [0059] 16. TPU-vi: F111 95A having a Tfb of 155° C. purchased from Jah Yih Enterprise Co. Ltd.; [0060] 17. TPU-vii: F111 85A having a Tfb of 140° C. purchased from Jah Yih Enterprise Co. Ltd.

Manufacturing Parameters of the Method of Producing a Reprocessed Material of rPVB

[0061] (1) Parameter Condition I: [0062] Step (A): First, a certain amount of fragmented rPVB and zinc stearate were put in a kneader together, and then they continued compounding at 60° C. until a dough-like first mixture was formed. Step (b1): Next, a part of the free radical initiator (such as an organic peroxide) was added into the first mixture when the first mixture was mixed and heated until the material temperature reached 70° C.; and then the remaining free radical initiator such as an azo compound were divided into three parts which were added into the first mixture in batches. After a completion of the reaction, the first intermediate was obtained. Step (b2): the first intermediate was heated to 110° C., followed by adding the desired additive(s) into the first intermediate which continued being mixed for 5 minutes; finally, the finished product by compounding passed through a single screw extruder underwater pelletizing machine to pelletize, followed by using a double-roller calender to output a reprocessed material of rPVB which had a shape of thin-film whose thickness was 0.3 millimeters (mm). [0063] (2) Parameter Condition II: [0064] Step (A): First, a certain amount of fragmented rPVB and zinc stearate were put in a kneader together, and then they continued compounding at 80° C. until a dough-like first mixture was formed. Step (b1): Next, a part of the free radical initiator (such as an organic peroxide) was added into the first mixture when the first mixture was mixed and heated until the material temperature reached 100° C.; and then the remaining free radical initiator such as an azo compound were divided into three parts which were added into the first mixture in batches. After a completion of the reaction, the first intermediate was obtained. Step (b2): the first intermediate was heated to 120° C., followed by adding the desired additive(s) into the first intermediate which continued being mixed for 5 minutes; finally, the finished product by compounding passed through a single screw extruder underwater pelletizing machine to pelletize, followed by using a double-roller calender to output a reprocessed material of rPVB which had a shape of thin-film whose thickness was about 0.3 mm.

Reprocessed Material of rPVB

[0065] All reprocessed materials of rPVB of Examples were respectively produced according to the content of each ingredient (weight unit: gram (g)) and the parameter condition shown in Table 1 and Table 2. Take the reprocessed material of rPVB E1 of Example 1 for example.

[0066] First, 1000 g of fragmented rPVB-1 and 10 g of zinc stearate were put in a kneader together, and then they continued compounding at 60° C. until a dough-like first mixture was formed. Next, 1 g of LPO was added into the first mixture when the first mixture was mixed and heated until the material temperature reached 70° C.; and then 25 g of AIBN was divided into three parts which were added into the first mixture in batches. After a completion of the reaction, the first intermediate was obtained. In this example, the completion of the reaction was determined by detecting the MI of the first intermediate until the MI almost had no fluctuation. Subsequently, the first intermediate was heated to 110° C., followed by adding the UV absorber and the antioxidant into the first intermediate which continued being mixed for 5 minutes; finally, the finished product by compounding passed through a single screw extruder underwater pelletizing machine to pelletize, followed by using a double-roller calender to output the reprocessed material of rPVB E1 which had a shape of thin-film.

Reference Example 1 (PIR PVB)

[0067] 100 g of fragmented rPVB-1 and 2 g of zinc stearate were put in a kneader together, and then they continued compounding at 110° C. for 5 minutes until they were mixed uniformly to form a mixture. Next, the mixture was put into the double-roller calender to output the reprocessed material of rPVB R1 which had a shape of thin-film.

Reference Example 2 (PCR PVB)

[0068] 100 g of fragmented rPVB-2 and 2 g of zinc stearate were put in a kneader together, and then they continued compounding at 110° C. for 5 minutes until they were mixed uniformly to form a mixture. Next, the mixture was put into the double-roller calender to output the reprocessed material of rPVB R2 which had a shape of thin-film.

Characteristic Analysis of the Reprocessed Material of rPVB

[0069] The reprocessed materials of rPVB E1 to E8 and the reprocessed materials of rPVB R1 and R2 were respectively analyzed by the following methods for MI, tensile strength, ultimate elongation in percent and tearing strength, and the results were listed in Table 1 and Table 2. In addition, the reprocessed materials of rPVB E1 to E8 and the reprocessed materials of rPVB R1 and R2 were also respectively analyzed by a dynamic mechanical analyzer (DMA) to obtain their respective glass transition temperature (Tg) and its loss tangent (tanδ), Tfb and its tanδ, and the results were also recorded in Table 1 and Table 2. In order to ensure the experimental significance and validity of the characteristic analysis, the reprocessed materials of rPVB E1 to E8 and R1 and R2 were each respectively analyzed by the same test method. Therefore, it can be understood that the difference in characteristics between the reprocessed materials of rPVB E1 to E8 and R1 and R2 was mainly caused by the difference in the free radical initiators and/or the parameter conditions used in each of the manufacturing methods.

Analysis

[0070] 1. MI: measured at a temperature of 190° C. and under 2.16 kg of load in accordance with the standard ASTM D1238 A; [0071] 2. Tensile strength: measured in accordance with the standard ASTM D412; [0072] 3. Ultimate elongation in percent: measured in accordance with the standard ASTM D412; [0073] 4. Tearing strength: measured in accordance with the standard ASTM D624; [0074] 5. Tg and its tanδ: measured in accordance with the standard ASTM D4065; [0075] 6. Tfb and its tanδ: measured in accordance with the standard ASTM D4065.

TABLE-US-00001 Example/ Reference Example No. E1 E2 E3 E4 E5 rPVB-1 1000.00 4000.00 1000.00 3000.00 3000.00 rPVB-2 0 0 0 0 0 Antiblocking Agent 10.00 20.00 10.00 35.00 35.00 Azo Compound I 25.00 75.00 25.00 75.00 75.00 Azo Compound II 0 0 0 0 0 Azo Compound III 0 0 0 0 0 Organic Peroxide a 1.00 0 0 1.50 0 UV Absorber 4.00 16.00 4.00 12.00 12.00 Antioxidant 2.00 8.00 2.00 6.00 6.00 Parameter Condition No. (I) (I) (I) (I) (I) MI (g/10 min) 15.80 9.60 9.10 14.13 10.60 Tensile Strength (kg/cm.sup.2) 279.50 268.50 286.97 167.94 167.94 Ultimate Elongation in percent (%) 246.00 234.50 218.95 223.91 223.91 Tearing Strength (kg/cm) 41.50 45.00 58.00 28.98 28.98 Tg (°C) 26.29 27.85 28.94 27.55 28.15 Tanδ at Tg 1.25 1.21 1.20 1.19 1.22 Tfb (°C) 123.77 129.79 130.37 126.13 129.22 Tanδ at Tfb 1.02 1.07 1.01 1.03 1.00

TABLE-US-00002 Example/ Reference Example No. E6 E7 E8 R1 R2 rPVB-1 3000.00 3000.00 0 100 0 rPVB-2 0 0 5500.00 0 100 Antiblocking Agent 30.00 30.00 55.00 2.00 2 Azo Compound I 75.00 75.00 137.50 0 0 Azo Compound II 0 0 0 0 0 Azo Compound III 0 0 0 0 0 Organic Peroxide a 0 0 0 0 0 Organic Peroxide b 1.50 1.50 2.75 0 0 UV Absorber 12.00 12.00 22.00 0 0 Antioxidant 6.00 6.00 11.00 0 0 Parameter Condition No. (I) (I) (II) - - - - Tensile Strength (kg/cm.sup.2) 255.01 270.82 185.01 266.00 163.7 Ultimate Elongation in percent (%) 242.86 241.00 194.77 263.00 208.2 Tearing Strength (kg/cm) 39.79 37.03 37.43 45.00 30 Tg (°C) 29.91 30.52 25.22 28.60 29.46 Tanδ at Tg 1.23 1.23 1.23 1.15 1.28 Tfb (°C) 131.95 124.83 127.21 132.18 125.16 Tanδ at Tfb 1.03 1.01 1.03 1.03 1.00

[0076] As shown in Tables 1 and 2, compared to the reprocessed material of rPVB R1 of Reference Example 1, each of the reprocessed materials of rPVB E1 to E7 of Examples 1 to 7 which comprised the same rPVB-1 but was obtained by the method of the present invention indeed had a higher MI (larger than 9 g/10 min) than that of the reprocessed material of rPVB R1 (4.34 g/10 min). Similarly, compared to the reprocessed material of rPVB R2 of Reference Example 2, the reprocessed material of rPVB E8 of Example 8 which comprised the same rPVB-2 but was obtained by the method of the present invention indeed had a higher MI (larger than 13 g/10 min) than that of the reprocessed material of rPVB R2 (4.09 g/10 min). It can demonstrate that the reprocessed materials of rPVB obtained by the method of the present invention has better reprocessabilty.

[0077] In addition, when the tanδ at the Tg point is greater than or equal to 1 in the DMA analysis, the test sample is considered as a material having a function of absorbing shock and a property of low rebound. Accordingly, from the results of DMA analyses in Table 1 and Table 2, it showed that the reprocessed materials of rPVB obtained by the method of the present invention can have properties of shock absorption and low rebound.

Hot Melt Adhesive

[0078] Hot melt adhesives of Examples were respectively produced in accordance with the content of each ingredient (weight unit: gram (g)) shown in Table 3. Take the hot melt adhesive HMA-1 of Example 9 for example. 4000 g of the reprocessed material of rPVB E4, 5000 g of TPU-i and 1000 g of TPU-iii were put in a kneader together, and then they continued compounding at 145° C. to obtain a finished product. Finally, the finished product by compounding passed through a single screw extruder underwater pelletizing machine to pelletize, followed by using a single-screw T-Die extruded machine to output the hot melt adhesive HMA-1 which had a shape of thin-film.

Characteristic Analysis of the Hot Melt Adhesive

[0079] The hot melt adhesives HMA-1 to HMA-5 were respectively analyzed by the following methods for MI, Tfb and adhesion tests, and the results were listed in Table 3. In order to ensure the experimental significance and validity of the characteristic analysis, the hot melt adhesives HMA-1 to HMA-5 were each respectively analyzed by the same test method. Therefore, it can be understood that the difference in characteristics between the hot melt adhesives HMA-1 to HMA-5 was mainly caused by the difference in the raw materials used for the hot melt adhesives HMA-1 to HMA-5.

Analysis

[0080] 1. MI: measured at a temperature of 190° C. and under 2.16 kg of load in accordance with the standard ASTM D1238 A; [0081] 2. Tfb: measured by the DMA in accordance with the standard ASTM D4065; [0082] 3. Adhesion Test (I): to measure the adhesion strength of the hot melt adhesive bonding between a TPU film and a fabric in accordance with G-44 of Nike standard measurement; [0083] 4. Adhesion Test (II): to measure the adhesion strength of the hot melt adhesive bonding between two PU films in accordance with G-44 of Nike standard measurement; [0084] 5. Adhesion Test (III): to measure the adhesion strength of the hot melt adhesive bonding between two TPU films in accordance with G-44 of Nike standard measurement.

[0085] When the measured adhesion strength of the hot melt adhesive obtained in Adhesion Tests (I) to (III) was equal to or larger than 2.5 N/mm, it was determined as passing the criterion of G-44 of Nike standard measurement.

TABLE-US-00003 Example No./ HMA No. E9/ HMA-1 E10/ HMA-2 E11/ HMA-3 E12/ HMA-4 E13/ HMA-5 Reprocessed Material of rPVB E1 0 0 0 0 0 E2 0 0 0 0 0 E3 0 0 0 0 0 E4 4000 0 0 0 0 E5 0 4000 0 0 0 E6 0 0 2160 0 0 E7 0 0 0 2000 0 E8 0 0 0 0 2000 TPU-i 5000 0 2700 2500 2500 TPU-ii 0 5000 0 0 0 TPU-iii 1000 1000 540 500 500 MI 16.00 13.00 21.13 4.51 39.60 Adhesion Test (I) Adhesion Strength (N/mm) 3.2-4.9 3.0-3.2 3.5-4.8 3.0-3.7 3.0-4.1 Adhesion Test (II) Adhesion Strength (N/mm) 5.4 3.6-4.0 4.6-4.8 3.8-4.1 4.8 Adhesion Test (III) Adhesion Strength (N/mm) 4.4-4.8 3.0-3.4 4.2-4.5 4.3-4.8 4.8

[0086] As shown in Table 3, the hot melt adhesives comprising the reprocessed material of rPVB of the present invention each had a Tfb not larger than 120° C., which conformed to the basic requirement of a hot melt adhesive.

[0087] In addition, all of the hot melt adhesives HMA-1 to HMA-5 respectively had an adhesion strength of larger than 2.5 N/mm in Adhesion Tests (I) to (III), so they all passed the criterion of G-44 of Nike standard measurement of having adhesion strength of “larger than or equal to 2.5 N/mm”. It can be seen that the reprocessed material of rPVB of the present invention can be applied to a hot melt adhesive because of the high MI thereof; therefore, the resulting hot melt adhesive not only satisfies the requirement of adhesion strength but also conforms to the global sustainability and circularity trends to implement the concept of environmental protection.

Composite Material Film

[0088] Composite material films of Examples were respectively produced in accordance with the content of each ingredient (weight unit: gram (g)) shown in Table 4. Take the composite material film CMF-1 of Example 14 for example. 400 g of the reprocessed material of rPVB E6 and 600 g of TPU-iv were put in a kneader together, and then they continued compounding at 145° C. to obtain a finished product. Finally, the finished product by compounding passed through a single screw extruder underwater pelletizing machine to pelletize, followed by using a single-screw T-Die extruded machine to output the composite material film CMF-1 which had a shape of thin-film. The composite material film CMF-1 had a thickness of about 0.3 mm.

Characteristic Analysis of the Composite Material Film

[0089] The composite material films CMF-1 to CMF-3 were respectively analyzed by the following methods for MI, Tfb, tensile strength, ultimate elongation in percent and tearing strength, and the results were listed in Table 4. In order to ensure the experimental significance and validity of the characteristic analysis, the composite material films CMF-1 to CMF-3 were each respectively analyzed by the same test method. That is, it can be understood that the difference in characteristics between the composite material films CMF-1 to CMF-3 was mainly caused by the difference in the raw materials used for the composite material films CMF-1 to CMF-3.

Analysis

[0090] 1. MI: measured at a temperature of 190° C. and under 2.16 kg of load in accordance with the standard ASTM D1238 A; [0091] 2. Tfb: measured by the DMA in accordance with the standard ASTM D4065; [0092] 3. Tensile strength: measured in accordance with the standard ASTM D412; [0093] 4. Ultimate elongation in percent: measured in accordance with the standard ASTM D412; [0094] 5. Tearing strength: measured in accordance with the standard ASTM D624.

TABLE-US-00004 Example No./ Composite Material Film No. E14/ CMF-1 E15/ CMF-2 E16/ CMF-3 Reprocessed Material of rPVB E1 0 0 0 E2 0 0 0 E3 0 0 0 E4 0 0 0 E5 0 0 0 E6 400 400 0 E7 0 0 300 E8 0 0 0 TPU-iv 600 600 0 TPU-v 0 0 0 TPU-vi 0 0 350 TPU-vii 0 0 350 MI 19.2 18.45 23.5 Tfb (°C) 120.68 121.43 145.68 Tensile Strength (kg/cm.sup.2) 220 210 224.1 Ultimate Elongation in percent (%) 420 350 330.6 Tearing Strength (kg/cm) 94 94 83.8

[0095] The composite material films CMF-1 and CMF-2 respectively had a Tfb of about 120° C., so they could be applied to the multilayered composite sheet suitable for high frequency weld process. Besides, since the composite material film CMF-3 had a higher Tfb (145° C.), it could be applied to the multilayered composite sheet that is suitable for high-temperature resistance.

[0096] In addition, in other embodiments, the TPU comprised in the composite material film may be a recycled TPU, so that raw materials of the composite material film can be a completely recycled composition, especially recycled resins.

[0097] From the results in Table 4, the rPVB content of the composite material film comprising the reprocessed material of rPVB of the present invention could be increased and the composite material film had good mechanical properties, so it indicated that the reprocessed material of rPVB of the present invention indeed has better reprocessability, thereby making all of the components of the composite material film mixed well; as a result, the deterioration of mechanical properties after film formation caused by inability to mix uniformly can be avoided.

[0098] Moreover, the composite material film can increase the use of recycled materials, so the composite material film of the present invention can reduce waste of global resource by using “sustainable” raw materials, and the concept of environmental protection will be implemented.

[0099] In summary, the method of producing a reprocessed material of rPVB of the present invention indeed can produce a reprocessed material of rPVB with a higher MI than that of the conventional reprocessed material of rPVB, so the reprocessability of the reprocessed material of rPVB can be improved, which broadens the subsequent applications and raises the market values.

[0100] Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and features of the disclosure, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.