TWI652296B - Constituent for producing shock-absorbing composite material, shock-absorbing composite material, and production method thereof - Google Patents

Abstract

The present invention provides a composition for preparing a shock absorbing composite material, comprising: a main substrate, which is 50-80 wt% of the total weight of the composition, comprising: vinyl acetate; an ethylene/vinyl acetate copolymer; a secondary substrate comprising from 10 to 40% by weight based on the total weight of the composition, comprising: polyethylene; styrene butadiene rubber; a thermoplastic elastomer; and an additive which is 1-20 of the total weight of the composition Wt%. Further, the present invention also provides a shock absorbing composite material using the above composition and a preparation method thereof. The shock absorbing composite material of the invention can be applied to sports product design (such as insole, club or racket, etc.), medical protection (such as protective clothing for old patients or disabled persons) or other related applications (such as safety) for reducing impact demand. Cap, car bumper, etc.). In addition, the shock absorbing composite material of the present invention can also be applied to the field of national defense industry.

Description

Composition for preparing shock absorbing composite material, shock absorbing composite material and preparation method thereof

The present invention relates to a composition for preparing a shock absorbing composite material, and more particularly to a composition for preparing a shock absorbing composite material comprising an ethylene/vinyl acetate copolymer. Further, the present invention relates to a shock absorbing composite material using the above composition and a method of producing the same.

In response to the development of modern industry and extreme leisure sports, solving vibration and shock has become a serious problem that urgently needs to be solved in various fields. Vibration and shock may cause problems such as reduced operational accuracy, shortened product life, hazardous personnel safety and environmental pollution. Therefore, how to absorb and reduce vibration and shock is an important key issue that we are trying to solve today.

The commonly used cushions generally have high rubber viscosity, poor oil resistance, poor vibration damping performance, poor impact resistance, low fatigue resistance and high cost. Although the shear thickening fluid has good vibration damping and impact resistance, its liquid form greatly reduces the practical application value.

The shear thickening fluid is a non-Newtonian fluid, which is special in that when the general composite fluid is subjected to shearing force, its viscosity is lowered, and the shear thickening fluid is in a certain range of viscosity. It is proportional to the shear force; this special property is why the shear thickening fluid hardens after being subjected to external forces.

Generally, the shear thickening flow system is a colloidal system composed of polyethylene glycol and cerium oxide composite. However, due to the strong hygroscopicity of polyethylene glycol, the colloidal system is unstable and not resistant to shearing.

Generally, the method for manufacturing the shock absorbing gasket is to mix and mix the substrate with various additive components, and mix the mixture at a predetermined temperature, and continue to foam molding in a specific mold to obtain a shock absorbing gasket. Depending on the substrate materials and additives used, there may be environmental protection issues in addition to the quality properties and production costs that may affect the finished product.

The colloidal solution is a shear thickening fluid. Because of its fluid properties, previous applications must be applied to the support to reduce the weight percentage of the shear thickening fluid in the shock absorbing composite (up to about 20 %wt). Through the technology of the invention, the shear thickening solution can be directly compounded and foamed and solidified, and the limitation of the previous application must be applied to the carrier, and the shock absorbing gasket can be integrally formed, without the problem of the proportion of the prior effective material. In turn, the shock absorption effect is enhanced.

The invention adopts the process technology of the vinyl acetate-based composite colloid, so that the energy dispersing colloid/vinyl acetate-based composition is foamed, shaped, and solidified into a desired shape in combination with a mold, and then combined with the structural requirements of the shock absorption. To complete the shock absorbing composite material, it can be widely used in personal body protection equipment, sports equipment protective equipment and packaging materials (covering materials) of precision instruments and 3C products.

It is an object of the present invention to provide a composition for preparing a shock absorbing composite material, whereby a shock absorbing composite material having impact resistance properties is obtained.

To achieve the above and other objects, the present invention provides a composition for preparing a shock absorbing composite comprising: a primary substrate comprising from 50 to 80% by weight based on the total weight of the composition, comprising: vinyl acetate; ethylene a vinyl acetate copolymer; a sub-substrate, which is 10-40% by weight based on the total weight of the composition, comprising: polyethylene; styrene butadiene rubber; thermoplastic elastomer; and an additive which occupies the combination The total weight of the object is 1-20 wt%.

In an embodiment of the present invention, the sub-substrate further comprises: a binary cerium oxide material, comprising: cerium oxide particles; and polydimethyl siloxane.

In one embodiment of the invention, the composition comprises: 9-18 wt% of a binary cerium oxide material.

In one embodiment of the invention, the ethylene vinyl acetate copolymer has a vinyl acetate content of from 60 to 90% by weight.

In one embodiment of the invention, the additive is selected from the group consisting of a blowing agent, a foaming aid, a bridging agent, a bridging aid, a color granule, and a filler.

In one embodiment of the invention, the composition comprises: 5-7 wt% vinyl acetate; and 45-63 wt% ethylene/vinyl acetate copolymer.

In one embodiment of the invention, the composition comprises: 6-18 wt% polyethylene; 3-6 wt% styrene butadiene rubber; and 2-4 wt% thermoplastic elastomer.

In one embodiment of the invention, the thermoplastic elastomer system is Styrene Ethylene Butylene Styrene Block Copolymer (SEBS).

Another object of the present invention is to provide a shock absorbing composite material whereby better impact resistance is obtained.

To achieve the above and other objects, the present invention provides a shock absorbing composite material which is obtained by kneading a composition as described above and foam molding.

Another object of the present invention is to provide a method for preparing a shock absorbing composite material, thereby obtaining a shock absorbing composite material having better impact resistance.

To achieve the above and other objects, the present invention provides a method of preparing a shock absorbing composite comprising: kneading the above composition; and foam molding the above-described kneaded composition.

Thereby, the composition for absorbing the shock absorbing composite of the present invention, the shock absorbing composite material and the preparation method thereof can obtain the shock absorbing composite material having better impact resistance.

In order to fully understand the objects, features and advantages of the present invention, the present invention will be described in detail by the following specific embodiments and the accompanying drawings.

Example 1: Composition for preparing a shock absorbing composite

The compositions for preparing the shock absorbing composite materials of Examples 1-1 to 1-4 were formulated according to the formulation ratios shown in Table 1, but the present invention is not limited thereto. Table 1  <TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td></td><td> Example 1-1 </td><td> Example 1-2 </td><td> Example 1-3 </td><td> Example 1-4 </td></tr><tr><td> Primary substrate </td><td > VA (%) </td><td> 7 </td><td> 7 </td><td> 5 </td><td> 5 </td></tr><tr><td > EVA (%) </td><td> 63 </td><td> 63 </td><td> 45 </td><td> 45 </td></tr><tr><td > Sub-substrate</td><td> PE (%) </td><td> 6 </td><td> 15 </td><td> 12 </td><td> 18 </td ></tr><tr><td> SBR (%) </td><td> 3 </td><td> 3 </td><td> 6 </td><td> 6 </td ></tr><tr><td> SEBS (%) </td><td> 2 </td><td> 2 </td><td> 4 </td><td> 4 </td ></tr><tr><td> Binary bismuth oxide material (%) </td><td> 9 </td><td> 0 </td><td> 18 </td><td > 12 </td></tr><tr><td> Additives</td><td> Foaming Agent (%) </td><td> 2.5 </td><td> 2.5 </td> <td> 2.5 </td><td> 2.5 </td></tr><tr><td> Foaming Aid (%) </td><td> 1.5 </td><td> 1.5 < /td><td> 1.5 </td><td> 1.5 </td></tr><tr><td> Bridging Agent (%) </td><td> 0.8 </td><td> 0.8 </td><td> 0.8 </td><td> 0.8 </td></tr><tr><td> Bridge Support (%) </td><td> 0.7 </td><td> 0.7 </td><td> 0.7 </td><td> 0.7 </td></tr><tr><td> Grain (%) </td><td> 0.5 </td><td> 0.5 </td><td> 0.5 </td><td> 0.5 </td></tr><tr><td> Filler (%) </td><td> 4 </td><td> 4 </td><td> 4 </td><td> 4 </td></tr></TBODY>< /TABLE>

The proportions of the components in Table 1 are all expressed by weight percentage. Wherein, VA stands for Vinyl acetate; EVA stands for Ethylene-vinyl acetate; PE stands for Polyethylene; SBR stands for Styrene Butadiene rubber; SEBS stands for Styrene Ethylene Butylene Styrene Block Copolymer, which is a thermoplastic elastomer which is commercially available from the market.

The preparation method of the binary cerium oxide material contained in the sub-substrate of Examples 1-1 to 1-4 is as described in the publication of the Republic of China Invention Patent No. 201602244, the entire contents of which are incorporated by reference. Incorporated herein.

The above binary cerium oxide material is prepared by the following method:

Step 1: Take cerium oxide particles with a particle size between 50 nm and 500 μm, and polydimethyl methoxy oxane with a molecular weight between 200 and 5000, and add appropriate amount of additives to stir evenly to form cerium oxide. And a mixed solution of polydimethyloxane, the mixed solution is allowed to uniformly distribute the microbubbles in the mixed solution to form a colloidal solution raw material, wherein the cerium oxide particles and polydimethyl siloxane are The mixing ratio is between 12 and 60% wt.

Step 2: adding the colloidal solution raw material to an appropriate amount of the crosslinking agent and stirring until uniform to form a colloidal solution plastic material, and the crosslinking agent may be a siloxane main monomer or a high molecular polymer thereof (such as PU or EVA, etc.).

Step 3: Filling the colloidal solution plastic material into the mold. The mold is made according to the impact energy absorption requirement, combined with the professional techniques such as impact stress simulation analysis and structural design. The material can be metal with temperature resistance above 200 °C, and the surface can be Passivation treatment to facilitate demolding, and heating to solidify and form, to form a binary cerium oxide material, the heating temperature is between 80 ~ 120 ° C, and the heating time is between 2 ~ 4 hours.

Embodiment 2: shock absorbing composite material and preparation method thereof

Example 2-1:

The preparation method of the shock absorbing composite material of Embodiment 2-1 is as shown in FIG. 1 , and the steps thereof include: Step 1 S101, kneading the composition as described in Example 1-1; and Step 2 S102, mixing the above-mentioned kneading The composition is foam molded. Thereby, the shock absorbing composite material of Example 2-1 was obtained. In this embodiment, the shock absorbing composite material is made into a shock absorbing gasket having a thickness of 20 mm for subsequent processing and testing.

In the above step 1, the mixing method and the processing conditions are not particularly limited as long as the respective components in the composition described in Example 1-1 can be sufficiently mixed. Preferably, the composition described in Example 1-1 is first placed in a kneader to carry out the first stage of mixing, mixing into a plastic mixture, and the process temperature is preferably controlled between 80 ° C and 150 ° C, and kneading. The time is preferably 15 to 30 minutes. Subsequently, the plastic mixture is further mixed and kneaded by a double roller, and the process temperature is preferably controlled between 80 ° C and 130 ° C, and the mixing time is preferably 3 to 6 minutes.

In the second step described above, the foam molding method and the process conditions are not particularly limited, and a foam molding method known in the art to which the present invention pertains can be used. Preferably, the foaming is performed by one-time foaming, and the briquetting foaming is performed by using a batch type hydraulic press, and the process temperature is preferably controlled between 130 ° C and 160 ° C, and the foaming molding time is preferably 30 to 50 minutes. The foaming limit pressure of the hydraulic press is preferably from 150 kg/cm ² to 250 kg/cm ² .

Example 2-2:

The preparation method of the shock absorbing composite of Example 2-2 was substantially the same as that of Example 2-1, but in the first step, the composition as described in Examples 1-2 was kneaded.

Example 2-3:

The preparation method of the shock absorbing composite material of Example 2-3 was substantially the same as that of Example 2-1, but in the first step, the composition as described in Examples 1-3 was kneaded.

Example 2-4:

The preparation method of the shock absorbing composite material of Example 2-4 was substantially the same as that of Example 2-1, but in the first step, the composition as described in Examples 1-4 was kneaded.

Test case:

According to the standard of 20kN (EN 1621-1:2012 motorcycle protective clothing impact specification, and TM142 energy absorption test, under the impact energy of 50 J, respectively, the shock absorbing composite materials of Examples 2-1~2-4 The test is carried out. The test results are shown in the following list 2. Table 2  <TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> </td><td> Example 2-1 </td><td> Example 2-2 </td><td> Example 2-3 </td><td> Example 2-4 </td></tr><tr><td> EN1621 Impact Test (KN) </td ><td> P1:10.4 P2:10.0 P3:10.3 </td><td> P1:62.2 P2:63.7 P3:59.5 </td><td> P1:9.01 P2:9.12 P3:9.03 </td>< Td> P1:9.11 P2:9.19 P3:9.57 </td></tr><tr><td> TM142 Energy Absorption Test (g) </td><td> 15 </td><td> 24 </ Td><td> 15 </td><td> 15 </td></tr></TBODY></TABLE>

It can be seen from the above test results that after the foaming and curing process of the composition for preparing the shock absorbing composite of the present invention, the prepared shock absorbing composite material conforms to the standard of low g energy absorption. The shock absorbing composite can be applied to sporting goods design (such as insoles, clubs or rackets), medical protection (such as clothing for the elderly or the disabled) or other related applications (such as helmets) that have reduced impact requirements. Car bumper, etc.). In addition, the shock absorbing composite material of the present invention can also be applied to the field of national defense industry.

The invention has been described above in terms of the preferred embodiments, and it should be understood by those skilled in the art that the present invention is not intended to limit the scope of the invention. It should be noted that variations and permutations equivalent to those of the embodiments are intended to be included within the scope of the present invention. Therefore, the scope of protection of the present invention is defined by the scope of the patent application.

S101‧‧‧Step one

S102‧‧‧Step two

Fig. 1 is a flow chart showing a method of preparing a shock absorbing composite material of Example 2-1 of the present invention.

Claims (10)

A composition for preparing a shock absorbing composite comprising: a primary substrate comprising from 50 to 80% by weight based on the total weight of the composition, comprising: vinyl acetate; an ethylene/vinyl acetate copolymer; a sub-substrate, It comprises from 10 to 40% by weight of the total weight of the composition, and comprises: polyethylene; styrene butadiene rubber; thermoplastic elastomer; and an additive which is from 1 to 20% by weight based on the total weight of the composition. The composition of claim 1, wherein the secondary substrate further comprises: a binary cerium oxide material comprising: cerium oxide particles; and polydimethyl methoxy oxane. The composition of claim 2, wherein the composition comprises: 9-18 wt% of a binary cerium oxide material. The composition of claim 1 wherein the ethylene/vinyl acetate copolymer has a vinyl acetate content of from 60 to 90% by weight. The composition of claim 1, wherein the additive is selected from the group consisting of a blowing agent, a foaming aid, a bridging agent, a bridging aid, a color granule, and a filler. The composition of claim 1, wherein the composition comprises: 5 to 7 wt% of vinyl acetate; and 45 to 63 wt% of an ethylene/vinyl acetate copolymer. The composition of claim 1, wherein the composition comprises: 6-18 wt% polyethylene; 3-6 wt% styrene butadiene rubber; and 2-4 wt% thermoplastic elastomer. The composition of claim 1 wherein the thermoplastic elastomer system is a styrene ethylene butylene styrene block copolymer. An shock absorbing composite material obtained by kneading the composition according to any one of claims 1 to 8, and foam molding. A method of preparing a shock absorbing composite material, comprising: kneading the composition according to any one of claims 1 to 8; and foam molding the above-described kneaded composition.