Foam composition and foam produced therefrom

Abstract

A foam composition comprises a recycled polyvinyl butyral in an amount from 5 wt % to 70 wt %; an ethylene-ester copolymer in an amount from 10 wt % to 70 wt %; a foaming agent in an amount from 0.5 wt % to 3.5 wt %; a peroxide crosslinking agent in an amount from 0.5 wt % to 3.0 wt %; and a hydrazide crosslinking agent in an amount from 0.1 wt % to 2.5 wt %, based on a total weight of the foam composition. A foam produced from the foam composition can avoid emitting an unpleasant odor of aldehydes, and the foam also has good mechanical properties and good resilience.

Claims

1. A foam composition comprising: a recycled polyvinyl butyral in an amount from 5 wt % to 70 wt % based on a total weight of the foam composition; an ethylene-ester copolymer in an amount from 10 wt % to 70 wt % based on the total weight of the foam composition; a foaming agent in an amount from 0.5 wt % to 3.5 wt % based on the total weight of the foam composition; a peroxide crosslinking agent in an amount from 0.5 wt % to 3.0 wt % based on the total weight of the foam composition; and a hydrazide crosslinking agent in an amount from 0.1 wt % to 2.5 wt % based on the total weight of the foam composition.

2. The foam composition as claimed in claim 1, wherein the hydrazide crosslinking agent is selected from the group consisting of: a monohydrazide compound, a dihydrazide compound, a polyhydrazide compound, and any combination thereof.

3. The foam composition as claimed in claim 2, wherein the hydrazide crosslinking agent is the dihydrazide compound, and the dihydrazide compound is selected from the group consisting of: succinic dihydrazide, adipic acid dihydrazide, azelaic acid dihydrazide, sebacic acid dihydrazide, and any combination thereof.

4. The foam composition as claimed in claim 1, wherein the peroxide crosslinking agent is selected from the group consisting of: dicumyl peroxide, 2,5-dimethyl-2,5-di(tert-buytlperoxy)-3-hexyne, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, 1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane, tert-butyl cumyl peroxide, and any combination thereof.

5. The foam composition as claimed in claim 3, wherein the peroxide crosslinking agent is selected from the group consisting of: dicumyl peroxide, 2,5-dimethyl-2,5-di(tert-buytlperoxy)-3-hexyne, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane, 1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane, tert-butyl cumyl peroxide, and any combination thereof.

6. The foam composition as claimed in claim 1, wherein the ethylene-ester copolymer is selected from the group consisting of: an ethylene-vinyl acetate copolymer, an ethylene-methyl acrylate copolymer, an ethylene-ethyl acrylate copolymer, an ethylene-butyl acrylate copolymer, and any combination thereof.

7. The foam composition as claimed in claim 6, wherein the ethylene-ester copolymer is the ethylene-vinyl acetate copolymer; the ethylene-vinyl acetate copolymer is prepared by a copolymerization of vinyl acetate and ethylene monomers, wherein a content of the vinyl acetate monomer ranges from 8.0 wt % to 35 wt % based on a total weight of the vinyl acetate and ethylene monomers.

8. The foam composition as claimed in claim 1, wherein the foaming agent is selected from the group consisting of: azodicarbonamide, 4,4′-oxybis(benzenesulfonyl hydrazide), p-toluenesulfonyl hydrazide, sodium hydrogen carbonate, and any combination thereof.

9. The foam composition as claimed in claim 1, wherein the foam composition further comprises a thermoplastic polyolefin in an amount from 5.0 wt % to 20 wt % based on the total weight of the foam composition.

10. The foam composition as claimed in claim 9, wherein the thermoplastic polyolefin is selected from the group consisting of: an ethylene propylene copolymer, an ethylene propylene diene terpolymer, an ethylene octene copolymer, an ethylene butylene copolymer, and any combination thereof.

11. The foam composition as claimed in claim 1, wherein the foam composition further comprises a rubber in an amount from 1.0 wt % to 20 wt % based on the total weight of the foam composition.

12. The foam composition as claimed in claim 1, wherein the foam composition further comprises an additive in an amount from 10 wt % to 29 wt % based on the total weight of the foam composition; wherein the additive is selected from the group consisting of: a foaming promotor, a peroxide crosslinking aid, a tackifier, a plasticizer, a lubricant, a filler, and any combination thereof.

13. The foam composition as claimed in claim 12, wherein the foaming promotor is selected from the group consisting of: zinc oxide, zinc octadecanoate, and a combination thereof; and the peroxide crosslinking aid is selected from the group consisting of: trimethylolpropane triacrylate, 2,4,6-triallyloxy-1,3,5-triazine, triallyl isocyanurate, N,N′-m-phenylene dimaleimide, and any combination thereof.

14. The foam composition as claimed in claim 9, wherein the foam composition further comprises a rubber, a foaming promotor, and a peroxide crosslinking aid; and wherein based on the total weight of the foam composition, the recycled polyvinyl butyral is in an amount from 40 wt % to 60 wt %; the ethylene-ester copolymer is in an amount from 10 wt % to 30 wt %; the foaming agent is in an amount from 1.0 wt % to 2.0 wt %; the peroxide crosslinking agent is in an amount from 0.5 wt % to 1.5 wt %; the hydrazide crosslinking agent is in an amount from 0.5 wt % to 1.5 wt %; the thermoplastic polyolefin is in an amount from 10 wt % to 15 wt %; the rubber is in an amount from 5.0 wt % to 10 wt %; the foaming promotor is in an amount from 0.5 wt % to 1.2 wt %; and the peroxide crosslinking aid is in an amount from 0.3 wt % to 1.0 wt %.

15. A foam produced from the foam composition as claimed in claim 1.

Description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(1) Hereinafter, one skilled in the arts can easily realize the advantages and effects of a foam composition and a foam thereof in accordance with the present invention from the following 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.

(2) Raw Materials

(3) 1. Recycled PVB: purchased from Protrade Asia Limited;

(4) 2. EVA: wherein product model is UE629, manufactured by USI Corporation, containing 18 wt % of vinyl acetate units;

(5) 3. Recycled EVA: recovered from scrap materials of foaming EVA products;

(6) 4. Thermoplastic polyolefin: ethylene octene copolymer; wherein product model is Solumer 865, manufactured by SK Global Chemical Co., Ltd.;

(7) 5. Rubber: brominated isobutylene isoprene rubber; wherein product model is Bromobutyl 2211, manufactured by Exxon Mobil Corporation;

(8) 6. Tackifier: wherein product model is Foral 85, manufactured by Eastman Chemical Company;

(9) 7. Foaming agent: azodicarbonamide; wherein product model is Celogen754A, manufactured by Celchem LLC;

(10) 8. Dicumyl peroxide: wherein product model is Luperox DC40, manufactured by Arkema;

(11) 9. Succinic acid dihydrazide: wherein product model is SDH, manufactured by Oakwood Chemical;

(12) 10. Foaming promotor: zinc oxide; purchased from Zinc Corp of America;

(13) 11. Peroxide crosslinking aid: triallyl isocyanurate; wherein product model is TAIL, manufactured by Mitsubishi International Polymer Trade;

(14) 12. Lubricant: stearic acid; wherein product model is Stearic Acid manufactured, by Wei-Chuang Technical Materials;

(15) 13. Filler: calcium carbonate; wherein product model is Light Calcium Carbonate, manufactured by Etana Industrial Co., Ltd.; and

(16) 14. Filler: silica; wherein product model is Ultrasil VN3, manufactured by Evonik Industries.

(17) Foam Composition

EXAMPLE 1 (E1)

(18) First, the recycled PVB was placed in a kneader and kneaded for 10 minutes. Next, EVA, succinic acid dihydrazide, calcium carbonate, silica, zinc oxide, triallyl isocyanurate, and stearic acid were added to the kneader and stirred at a temperature of 120° C. for 12 minutes. At the last 2 minutes of the aforesaid mixing step, azodicarbonamide and dicumyl peroxide were added to the kneader and mixed for 2 minutes to obtain a mixture. Subsequently, the mixture was transferred to a double roller which raised the temperature, and then the mixture was transferred to a dispersing roller to obtain a uniform foam composition, called Foam Composition 1. The components of Foam Composition 1 were as follows: 54.6 wt % of recycled PVB, 23.4 wt % of EVA, 0.8 wt % of succinic acid dihydrazide, 13 wt % of calcium carbonate, 3.8 wt % of silica, 1.5 wt % of zinc oxide, 0.3 wt % of triallyl isocyanurate, 0.5 wt % of stearic acid, 1.4 wt % of azodicarbonamide, and 0.7 wt % of dicumyl peroxide.

(19) Foam

(20) Foam Composition 1 was placed in an open mixing mill and then processed with a sequential step of mixing, plastifying, and calendaring at 80° C. to obtain a sheet-like film in a thickness of 1 cm.

(21) 150 grams cut from said film was placed in a mold, and the mold was put into a flat-panel vulcanizer, and Foam Composition 1 underwent compression molding for 10 minutes to 15 minutes at 165° C. to 170° C. and under a compression pressure of 7 kg to 8 kg to obtain Foam 1.

EXAMPLES 2 to 4 (E2 to E4)

COMPARATIVE EXAMPLES 1 to 4 (C1 to C4

(22) The foam compositions of Examples 2 to 4 were prepared according to the content ratios shown in Table 1, and then Foams 2 to 4 were prepared in the same procedure as in the preparation of Foam 1. The main difference between Foam Composition 1 of Example 1 and Foam Compositions 2 to 4 of Examples 2 to 4 was sources of EVA contained therein and weight ratios of recycled PVB and EVA.

(23) The foam compositions of Comparative Examples 1 to 4 were prepared according to the content ratios shown in Table 2, and then Foams 7 to 10 were prepared in the same procedure as in the preparation of Foam 1. The main difference between Example 1 and Comparative Examples 1 to 4 was the components contained therein and their weight ratios.

EXAMPLE 5 (E5)

(24) First, the recycled PVB was placed in a kneader and kneaded for 10 minutes. Next, EVA, the thermoplastic polyolefin, the rubber, the tackifier, succinic acid dihydrazide, calcium carbonate, silica, zinc oxide, triallyl isocyanurate, and stearic acid were added to the kneader and stirred at a temperature of 120° C. for 12 minutes. At the last 2 minutes of the aforesaid mixing step, azodicarbonamide and dicumyl peroxide were added to the kneader and mixed for 2 minutes to obtain a mixture. Subsequently, the mixture was transferred to a double roller which raised the temperature, and then the mixture was transferred to a dispersing roller to obtain a uniform foam composition, called Foam Composition 5. The components of Foam Composition 5 were as follows: 47 wt % of recycled PVB, 8.4 wt % of EVA, 15 wt % of the thermoplastic polyolefin, 6.7 wt % of the rubber, 6.7 wt % of the tackifier, 0.8 wt % of succinic acid dihydrazide, 8.5 wt % of calcium carbonate, 2.2 wt % of silica, 1.5 wt % of zinc oxide, 0.4 wt % of triallyl isocyanurate, 0.5 wt % of stearic acid, 1.6 wt % of azodicarbonamide, and 0.7 wt % of dicumyl peroxide.

(25) Foam Composition 5 was placed in an open mixing mill and then processed with a sequential step of mixing, plastifying, and calendaring at 80° C. to obtain a sheet-like film with a thickness of 1 cm.

(26) 150 grams cut from said film was placed in a mold, the mold was put into a flat-panel vulcanizer, and Foam Composition 5 underwent compression molding for 10 minutes to 15 minutes at 165° C. to 170° C. and under a compression pressure of 7 kg to 8 kg to obtain Foam 5.

EXAMPLE 6 (E6)

COMPARATIVE EXAMPLES 5 and 6 (C5 and C6)

(27) The foam composition of Example 6 was prepared according to the content ratios shown in Table 1, and then Foam 6 was prepared in the same procedure as in the preparation of Foam 5. The main difference between Foam Composition 5 of Example 5 and Foam Composition 6 of Example 6 was the components contained therein and their weight ratios.

(28) The foam compositions of Comparative Examples 5 and 6 were prepared according to the content ratios shown in Table 2, and then Foams 11 and 12 were prepared in the same procedure as in the preparation of Foam 5. The main difference between Example 5 and Comparative Examples 5 and 6 was the components contained therein and their weight ratios.

(29) TABLE-US-00001 TABLE 1 components of foam compositions of Examples 1 to 6 E1 E2 E3 E4 E5 E6 Recycled PVB 54.6 39 23.4 54.6 47 20.2 (wt %) Recycled EVA 0 0 0 23.4 0 0 (wt %) EVA (wt %) 23.4 39 54.6 0 8.4 28.8 Thermoplastic 0 0 0 0 15 6.7 polyolefin (wt %) Rubber (wt %) 0 0 0 0 6.7 13.5 Tackifier (wt %) 0 0 0 0 6.7 10.1 Stearic acid (wt %) 0.5 0.5 0.5 0.5 0.5 0.5 Zinc oxide (wt %) 1.5 1.5 1.5 1.5 1.5 1.5 Calcium carbonate 13 13 13 13 8.5 11 (wt %) Silica (wt %) 3.8 3.8 3.8 3.8 2.2 3.8 Azodicarbonamide 1.4 1.4 1.4 1.4 1.6 1.9 (wt %) Dicumyl peroxide 0.7 0.7 0.7 0.7 0.7 0.7 (wt %) TAIC (wt %) 0.3 0.3 0.3 0.3 0.4 0.5 Succinic acid 0.8 0.8 0.8 0.8 0.8 0.8 dihydrazide (wt %)

(30) TABLE-US-00002 TABLE 2 components of foam compositions of Comparative Examples 1 to 6 C1 C2 C3 C4 C5 C6 Recycled PVB 54.6 39 23.4 54.6 47 20.2 (wt %) Recycled EVA 0 0 0 23.4 0 0 (wt %) EVA (wt %) 23.4 39 54.6 0 8.4 28.8 Thermoplastic 0 0 0 0 15 6.7 polyolefin (wt %) Rubber (wt %) 0 0 0 0 6.7 13.5 Tackifier (wt %) 0 0 0 0 6.7 10.1 Stearic acid (wt %) 0.5 0.5 0.5 0.5 0.5 0.5 Zinc oxide (wt %) 1.5 1.5 1.5 1.5 1.5 1.5 Calcium carbonate 13.8 13.8 13.8 13.8 8.5 11.8 (wt %) Silica (wt %) 3.8 3.8 3.8 3.8 3 3.8 Azodicarbonamide 1.4 1.4 1.4 1.4 1.6 1.9 (wt %) Dicumyl peroxide 0.7 0.7 0.7 0.7 0.7 0.7 (wt %) TAIC (wt %) 0.3 0.3 0.3 0.3 0.4 0.5 Succinic acid 0 0 0 0 0 0 dihydrazide (wt %)

(31) Analysis:

(32) Foams 1 to 12 prepared from the foam composition of Examples 1 to 6 and Comparative Examples 1 to 12 were analyzed on the mechanical properties, volumetric expansion factor, hardness, specific gravity, and odor, and the results were listed in Tables 3 and 4. In order to ensure the experimental significance of the characteristic analysis, Foams 1 to 12 were each respectively formed in the same manner from the corresponding foam compositions, and Foams 1 to 12 were each analyzed by the same test method. Therefore, it can be understood that the difference in characteristics of each of Foams 1 to 12 was mainly caused by the difference in composition of each of the foam compositions.

(33) 1. Rheological properties (TS2): measured in accordance with the standard D5289 established by American Society for Testing and Materials (ASTM);

(34) 2. Rheological properties (TC90): measured in accordance with the standard ASTM D5289;

(35) 3. Maximum torque (M.sub.h): measured in accordance with the standard ASTM D5289;

(36) 4. Minimum torque (M.sub.1): measured in accordance with the standard ASTM D5289;

(37) 5. Volumetric expansion factor: every foam composition was put into a mold of a fixed size (length×width×height=140 cm×100 cm×15 cm), wherein there was a 100 cm groove in the bottom of the mold; when the foam thereof was formed, a new length of the groove was measured by a ruler (unit: centimeter), and the volumetric expansion factor was defined as the new length divided by 100;

(38) 6. Hardness (type C): measured in accordance with the standard ASTM D792-13;

(39) 7. Specific gravity: measured in accordance with the standard ASTM D792-13;

(40) 8. Rebound resilience: measured in accordance with the standard ASTM D2632-92; and

(41) 9. Odor test: evaluated by an olfactory test in which a same tester assessed the odors of Foams 1 to 12, respectively.

(42) TABLE-US-00003 TABLE 3 characteristics of Examples 1 to 6 and obtained Foams 1 to 6 Foam 1 Foam 2 Foam 3 Foam 4 Foam 5 Foam 6 Example No. E1 E2 E3 E4 E5 E6 Rheological 4′16″ 4′26″ 3′01″ 6′28″ 0′00″ 0′00″ properties (TS2) (min(′) sec(″)) Rheological 7′15″ 7′14″ 6′48″ 7′33″ 8′09″ 8′10″ properties (TC90) (min(′) sec(″)) Maximum 3.21 3.15 3.72 2.68 1.19 1.2 torque Minimum 0.19 0.26 0.3 0.71 0.21 0.27 torque Volumetric 175 175 175 155 175 175 expansion factor (%) Hardness 23 26 45-55 30 22 45 (type C) Specific gravity 0.13 0.125 0.12 0.14 0.135 0.125 (g/cm.sup.3) Rebound 15% 21% 26% 10-11% 17% 24% resilience (%) Odor test No odor

(43) TABLE-US-00004 TABLE 4 characteristics of Comparative Examples 1 to 6 and obtained Foams 7 to 12 Foam Foam Foam Foam Foam Foam 7 8 9 10 11 12 Example No. C1 C2 C3 C4 C5 C6 Rheological 7′31″ 6′20″ 6′58″ 7′10″ 0′00″ 0′00″ properties (TS2) (min(′) sec(″)) Rheological 8′37″ 8′09″ 8′38″ 8′20″ 8′28″ 8′36″ properties (TC90) (min(′) sec(″)) Maximum torque 2.67 2.88 2.99 2.34 1.02 1.07 Minimum torque 0.19 0.27 0.33 0.71 0.22 0.26 Volumetric 175 175 175 155 175 175 expansion factor (%) Hardness (type C) 21 23 40 27 20 39 Specific gravity 0.13 0.125 0.12 0.14 0.135 0.125 (g/cm.sup.3) Rebound resilience (%) 19% 25% 30% 15% 21% 29% Odor test Unpleasant odor

(44) As shown in Table 3, Foams 1 to 6 prepared from the foam composition including the hydrazide crosslinking agent (i.e., Examples 1 to 6) did not emit the unpleasant odor of the aldehydes. In contrast, as shown in Table 4, Foams 7 to 12 prepared from the foam composition without the hydrazide crosslinking agent (i.e., Comparative Examples 1 to 6) emitted unpleasant odor.

(45) In addition, in order to further compare the difference in characteristics of the foam compositions having similar compositions of the respective groups, the analytical results of Foam 1 obtained by the foam composition of Example 1 were compared with those of Foam 7 obtained by the foam composition of Comparative Example 1. Similarly, the analytical results of Foam 2 obtained by the foam composition of Example 2 were compared with those of Foam 8 obtained by the foam composition of Comparative Example 2. The comparisons can demonstrate the effect of adding the hydrazide crosslinking agent into the foam composition.

(46) From the comparisons of the rheological properties (TS2) in Tables 3 and 4, compared to the foam composition free of hydrazide crosslinking agent, the foam prepared from the foam composition including the hydrazide crosslinking agent would have a lower TS2 value. For example, the TS2 value of Foam 1 was reduced by about 43% compared to the TS2 value of Foam 7; the TS2 value of Foam 2 was reduced by about 30% compared to the TS2 value of Foam 8; the TS2 value of Foam 3 was reduced by about 57% compared to the TS2 value of Foam 9; and the TS2 value of Foam 4 was reduced by about 10% compared to the TS2 value of Foam 10. It illustrated that each of the foam compositions of Examples 1 to 4 had good fluidity at the initial reaction period, and thus all the components in the foam composition could be uniformly dispersed. Besides, since the foam compositions of Examples 5 and 6 contained the tackifier and the thermoplastic polyolefin and the tackifier was in a form of liquid at 170° C. while processing the compression foam molding, the reaction initiated from the peroxide crosslinking agent would be delayed. Therefore, said foam composition had a better fluidity at the initial reaction period.

(47) Moreover, from the comparisons of the rheological properties (TC90) in Tables 3 and 4, compared to the foam composition free of the hydrazide crosslinking agent, the foam prepared from the foam composition including the hydrazide crosslinking agent would have a lower TC90 value. For example, the TC90 value of Foam 1 was reduced by about 16% compared to the TC90 value of Foam 7; the TC90 value of Foam 2 was reduced by about 11% compared to the TC90 value of Foam 8; the TC90 value of Foam 3 was reduced by about 21% compared to the TC90 value of Foam 9; the TC90 value of Foam 4 was reduced by about 9% compared to the TC90 value of Foam 10; the TC90 value of Foam 5 was reduced by about 4% compared to the TC90 value of Foam 11; and the TC90 value of Foam 6 was reduced by about 5% compared to the TC90 value of Foam 12. It illustrated that time needed for 90% completion of Foams 1 to 6 was reduced. That is, the reaction rate of the foam composition was increased.

(48) From the comparisons of the maximum torque in Tables 3 and 4, compared to the foam composition free of hydrazide crosslinking agent, the foam prepared from the foam composition including the hydrazide crosslinking agent would have a higher M.sub.h value. Specifically, the M.sub.h value of Foam 1 was higher than the M.sub.h value of Foam 7; the M.sub.h value of Foam 2 was higher than the M.sub.h value of Foam 8; the M.sub.h value of Foam 3 was higher than the M.sub.h value of Foam 9; the M.sub.h value of Foam 4 was higher than the M.sub.h value of Foam 10; the M.sub.h value of Foam 5 was higher than the M.sub.h value of Foam 11; and the M.sub.h value of Foam 6 was higher than the M.sub.h value of Foam 12. It illustrated that each of Foams 1 to 6 had a better shear modulus, better elongation, and higher crosslinking density.

(49) In addition, from the comparisons of the hardness in Tables 3 and 4, compared to the foam composition free of hydrazide crosslinking agent, the foam prepared from the foam composition including the hydrazide crosslinking agent would have a higher hardness. Specifically, the hardness of Foam 1 was higher than the hardness of Foam 7; the hardness of Foam 2 was higher than the hardness of Foam 8; the hardness of Foam 3 was higher than the hardness of Foam 9; the hardness of Foam 4 was higher than the hardness of Foam 10; the hardness of Foam 5 was higher than the hardness of Foam 11; and the hardness of Foam 6 was higher than the hardness of Foam 12. It illustrated that each of Foams 1 to 6 had a higher hardness; that is, each of Foams 1 to 6 had an improved mechanical property.

(50) From the comparisons of the rebound resilience in Tables 3 and 4, the foam prepared from the foam composition including the hydrazide crosslinking agent would have a higher rebound resilience compared to the foam prepared from the foam composition free of hydrazide crosslinking agent. Specifically, the rebound resilience of Foam 1 was higher than the rebound resilience of Foam 7; the rebound resilience of Foam 2 was higher than the rebound resilience of Foam 8; the rebound resilience of Foam 3 was higher than the rebound resilience of Foam 9; the rebound resilience of Foam 4 was higher than the rebound resilience of Foam 10; the rebound resilience of Foam 5 was higher than the rebound resilience of Foam 11; and the rebound resilience of Foam 6 was higher than the rebound resilience of Foam 12. It illustrated that each of Foams 1 to 6 had a better deformation recovery ability.

(51) Based on the results in Tables 3 and 4, the use of the foam composition not only eliminates the unpleasant odor of aldehydes emitted from the prepared foam but also improves the mechanical properties of the foam, thus enhancing the application value of the foam composition and the foam thereof of the present invention.