阅读说明：本技术 一种带ip密封功能与emi功能的复合件及其成型方法 (Composite part with IP sealing function and EMI function and forming method thereof ) 是由 陈建 胡杨飞 胡星星 尚晨光 岳永林 冯志成 高文廷 张伟 黄伟 张佳凤 郑凌波 于 2020-04-17 设计创作，主要内容包括：本发明涉及一种带IP密封功能与EMI功能的复合件及其成型方法,其特征在于包括以下组分：其中A每一分子至少具有两个链烯基的有机聚硅氧烷100份；B每一分子具有至少两个硅键合的氢原子的有机聚硅氧烷5-25份；C白炭黑15-25份；D铂基催化剂0.05-0.15份；E抑制剂0.005-0.01份；F金属基导电填料250-500份；G稀释剂0-20份。本发明带IP密封功能与EMI功能的复合件及其成型方法,生产的复合件具有很好的粘度,能够有效的降低材料的成本,具有很好的高导电性,可以作为电磁屏蔽材料,广泛应用于导电壳体、手机电脑等电子设备。(The invention relates to a composite part with an IP sealing function and an EMI function and a forming method thereof, which is characterized by comprising the following components: wherein A has 100 parts of organopolysiloxane of at least two alkenyl groups per molecule; b5-25 parts per molecule of an organopolysiloxane having at least two silicon-bonded hydrogen atoms; 15-25 parts of C white carbon black; 0.05-0.15 part of platinum-based catalyst D; 0.005-0.01 part of E inhibitor; 500 portions of F metal-based conductive filler 250-; and 0-20 parts of G diluent. According to the composite part with the IP sealing function and the EMI function and the forming method thereof, the produced composite part has good viscosity, can effectively reduce the material cost, has good high conductivity, can be used as an electromagnetic shielding material, and can be widely applied to electronic equipment such as conductive shells, mobile phones and computers.)

1. A composite part with IP sealing function and EMI function is characterized by comprising the following components: wherein A has 100 parts of organopolysiloxane of at least two alkenyl groups per molecule;

b5-25 parts per molecule of an organopolysiloxane having at least two silicon-bonded hydrogen atoms;

15-25 parts of C white carbon black;

0.05-0.15 part of platinum-based catalyst D;

0.005-0.01 part of E inhibitor;

500 portions of F metal-based conductive filler 250-;

and 0-20 parts of G diluent.

2. The composite with IP sealing functionality and EMI functionality according to claim 1, characterized in that component B provides 1-5 mol of silicon-bonded hydrogen atoms from component B, based on 1 mol of alkene in component a.

3. The composite with IP sealing functionality and EMI functionality as claimed in claim 1, wherein said component C has a specific surface area of at least 200 m²Per g, fumed silica is preferred.

4. The composite with IP sealing functionality and EMI functionality according to claim 1, characterized in that the component C treatment agent comprises a silazane compound, preferably hexamethylsilazane.

5. The composite with IP sealing functionality and EMI functionality according to claim 1, characterized in that the component D is a platinum catalyst, preferably a platinum-on-cassett catalyst, wherein the platinum content is 3000 ppm.

6. The composite with IP sealing and EMI functionality according to claim 1, characterized in that the component E is an alkynol compound comprising 1-ethyne-1-cyclohexanol, 3-methyl-1-butyn-3-ol, 3, 5-dimethyl-1-hexyn-3-ol, 3-phenyl-1-butyn-3-ol.

7. The composite with IP sealing functionality and EMI functionality according to claim 1, characterized in that said component F comprises electrically conductive metal powder or metal plated micro powder by means of vapour deposition.

8. The composite with IP sealing functionality and EMI functionality according to claim 1, characterized in that said component G comprises a volatile organic solvent and a low viscosity silicone oil.

9. A molding method of a composite part with an IP sealing function and an EMI function is characterized by comprising the following steps:

s1 splitting the product, molding the IP part of the product, and setting the pressure of the molding press to 80-180 kg/cm²The molding temperature is 150-;

s2, placing the IP sealing piece after edge detachment into a mold compounded with EMI, positioning, and accurately injecting liquid conductive adhesive into a position corresponding to the IP sealing piece in a mode of self-injection holes in the mold after positioning is finished;

s3 compounding the IP part and the EMI part, specifically, putting the IP part into another pair of dies or replacing other structural parts of the dies, co-molding with the EMI part, and setting the pressure of a molding press to be 50-150kg/cm²The temperature is 100-120 ℃, and the vulcanization time is 150-300 seconds.

10. The method of claim 9, wherein the sealing portion between the mold and the product of the previous step is provided with a predetermined position greater than 0.20 mm;

the material used in the molding process comprises liquid glue or solid glue;

the feeding mode of the die comprises a mode of directly putting corresponding materials or transferring the materials;

when pan feeding shaping solidification, reduce the exhaust distance and the exhaust number of times of board self, adopt evacuation processing in order to ensure nest gas.

Technical Field

The invention relates to the field of rubber composite die forming, in particular to a composite part with an IP sealing function and an EMI function and a forming method thereof.

Background

Rubber molding refers to molding by various rubber molding machines, generally filler molding presses and extrusion molding. Compression molding is generally carried out by forcing a preform, which has been prepared for placement in a mold, into a mold cavity. Then through a certain time, temperature and pressure, the rubber material is subjected to chemical reaction (molecules are crosslinked to be in a net shape from a linear shape), so that the product with applicable performance is prepared.

The extrusion molding is generally a method of extruding the material through a die and then heating and vulcanizing the material or a method of directly heating the material by the die and extruding the material while vulcanizing the material. Sometimes, the part functioning as the IP may also function as a cost reduction function, for example, conventionally, the part functioning as the EMI function is made of a material much higher than other parts, so that the non-EMI material is adopted to replace the EMI material at the position of the product part, thereby achieving the function of reducing the cost. At the same time, the IP part can also be used for reducing (or increasing) the longitudinal force of the whole product. The conventional composite member having the IP function and the EMI shielding function is formed by extrusion, so that only a product having a fixed extrusion cross section can be extruded. And if the cross sections of the required products are different, the products cannot be formed in an extrusion forming mode.

Disclosure of Invention

In order to solve the technical problems, the invention adopts the following scheme:

a composite part with IP sealing function and EMI function is characterized by comprising the following components: wherein A has 100 parts of organopolysiloxane of at least two alkenyl groups per molecule;

b5-25 parts per molecule of an organopolysiloxane having at least two silicon-bonded hydrogen atoms;

15-25 parts of C white carbon black;

0.05-0.15 part of platinum-based catalyst D;

0.005-0.01 part of E inhibitor;

500 portions of F metal-based conductive filler 250-;

and 0-20 parts of G diluent.

The composite member with the IP sealing function and the EMI function is characterized in that the component B provides 1-5 mol of silicon-bonded hydrogen atoms from the component B based on 1 mol of alkene in the component A.

The composite part with the IP sealing function and the EMI function is characterized in thatThe specific surface area of the component C is at least 200 m²Per g, fumed silica is preferred.

The composite with IP sealing functionality and EMI functionality is characterized in that the component C treating agent comprises a silazane compound, preferably hexamethyl silazane.

The composite with IP sealing function and EMI function is characterized in that the component D is a platinum catalyst, preferably a Karster platinum catalyst, wherein the platinum content is 3000 ppm.

The composite part with the IP sealing function and the EMI function is characterized in that the component E is an alkynol compound and comprises 1-acetylene-1-cyclohexanol, 3-methyl-1-butine-3-ol, 3, 5-dimethyl-1-hexine-3-ol and 3-phenyl-1-butine-3-ol.

The composite member having an IP sealing function and an EMI function is characterized in that the component F includes a conductive metal powder or a metal plating micro powder by means of vapor deposition.

The composite member with IP sealing function and EMI function is characterized in that the component G comprises volatile organic solvent and low-viscosity silicone oil.

A molding method of a composite part with an IP sealing function and an EMI function is characterized by comprising the following steps:

s1 splitting the product, molding the IP part of the product, and setting the pressure of the molding press to 80-180 kg/cm²The molding temperature is 150-;

s2, placing the IP sealing piece after edge detachment into a mold compounded with EMI, positioning, and accurately injecting liquid conductive adhesive into a position corresponding to the IP sealing piece in a mode of self-injection holes in the mold after positioning is finished;

s3 compounding the IP part and the EMI part, specifically, putting the IP part into another pair of dies or replacing other structural parts of the dies, co-molding with the EMI part, and setting the pressure of a molding press to be 50-150kg/cm²The temperature is 100-120 ℃, and the vulcanization time is 150-300 seconds.

The molding method of the composite part with the IP sealing function and the EMI function is characterized in that a reserved position with the size larger than 0.20mm is arranged at the sealing position of the mold and a product in the previous step;

the material used in the molding process comprises liquid glue or solid glue;

the feeding mode of the die comprises a mode of directly putting corresponding materials or transferring the materials;

when pan feeding shaping solidification, reduce the exhaust distance and the exhaust number of times of board self, adopt evacuation processing in order to ensure nest gas.

The composite part with the IP sealing function and the EMI function and the forming method thereof have the following beneficial effects:

according to the composite part with the IP sealing function and the EMI function and the forming method thereof, the produced composite part has good viscosity, can effectively reduce the material cost, has good high conductivity, can be used as an electromagnetic shielding material, and can be widely applied to electronic equipment such as conductive shells, mobile phones and computers.

In addition, through the mould pressing compounding, the rubber compound piece has the IP sealing function and the EMI function simultaneously, the market demand for the multifunctional product is met, and the market competitiveness is improved.

Drawings

FIG. 1: the present invention provides a cross-sectional view of a composite with IP sealing and EMI functionality.

Description of reference numerals:

1IP functional part; 2EMI functional parts.

Detailed Description

The following detailed description of the embodiments of the present invention will be made with reference to the accompanying drawings, so that the technical solutions of the present invention can be understood and appreciated more easily.

The composite piece with the IP sealing function and the EMI function comprises the following components in parts by mass:

a100 parts of an organopolysiloxane having at least two alkenyl groups per molecule;

b5-25 parts per molecule of an organopolysiloxane having at least two silicon-bonded hydrogen atoms;

15-25 parts of C white carbon black;

0.05-0.15 part of platinum-based catalyst D;

0.005-0.01 part of E inhibitor;

500 portions of F metal-based conductive filler 250-;

and 0-20 parts of G diluent.

Wherein component B provides 1 to 5 moles of silicon-bonded hydrogen atoms from component B based on 1 mole of alkene in component A.

The specific surface area of the component C is at least 200 m²Per g, fumed silica is preferred, which is added in an amount of 10 to 25 parts per 100 parts of component A.

The component C treating agent is a silazane compound, preferably hexamethyl silazane, and is added in an amount of 5 to 15 parts by mass relative to 100 parts by mass of fumed silica.

Component D is a platinum catalyst, preferably a platinum-gold Casnst catalyst, with a platinum content of 3000 ppm, which is added in an amount of 0.05 to 0.15 parts per 100 parts of component A.

The component E is one of alkynol compounds, comprises 1-acetylene-1-cyclohexanol, 3-methyl-1-butyn-3-ol, 3, 5-dimethyl-1-hexyn-3-ol and 3-phenyl-1-butyn-3-ol, and is added in an amount of 0.005-0.0.01 parts relative to 100 parts of the component A.

Component F comprises a conductive metal powder or a metal plating micro powder for vapor deposition, which is added in an amount of 250-500 parts relative to 100 parts of component A.

The component G comprises a volatile organic solvent and a low-viscosity silicone oil, and is added in an amount of 0-20 parts relative to 100 parts of the component A.

The viscosity of the composite part with the IP sealing function and the EMI function is controlled between 2000-4000 Pa.s, so that the composite part is suitable for the common-mode molding of complex products, and the material cost is further reduced.

Has high conductivity with volume resistivity less than or equal to 0.1 omega cm, can be used as electromagnetic shielding material, and can be widely applied to electronic equipment such as conductive shells, mobile phones, computers and the like.

The composite parts with IP sealing function and EMI function produced by different components are respectively subjected to conductivity, dustproof and waterproof performance and viscosity detection.

Wherein test group one is 100 parts of organopolysiloxane having at least two alkenyl groups per molecule, 5 parts of organopolysiloxane having at least two silicon-bonded hydrogen atoms per molecule, 15 parts of white carbon black, 0.05 part of platinum-based catalyst, 0.005 part of inhibitor, 250 parts of nickel-coated graphite conductive filler, and 0 part of diluent.

Test group two was 100 parts of an organopolysiloxane having at least two alkenyl groups per molecule, 15 parts of an organopolysiloxane having at least two silicon-bonded hydrogen atoms per molecule, 20 parts of white carbon, 0.1 part of a platinum-based catalyst, 0.0075 parts of an inhibitor, 375 parts of a silver-plated glass conductive filler, and 10 parts of a diluent.

Test group three was 100 parts of an organopolysiloxane having at least two alkenyl groups per molecule, 25 parts of an organopolysiloxane having at least two silicon-bonded hydrogen atoms per molecule, 25 parts of white carbon, 0.15 part of a platinum-based catalyst, 0.01 part of an inhibitor, 500 parts of a silver-plated glass conductive filler, and 20 parts of a diluent.

Test group four was 100 parts of an organopolysiloxane having at least two alkenyl groups per molecule, 3 parts of an organopolysiloxane having at least two silicon-bonded hydrogen atoms per molecule, 10 parts of white carbon black, 0.02 part of a platinum-based catalyst, 0.003 part of an inhibitor, 200 parts of a nickel-coated graphite conductive filler, and 0 part of a diluent.

Test group five was 100 parts of an organopolysiloxane having at least two alkenyl groups per molecule, 30 parts of an organopolysiloxane having at least two silicon-bonded hydrogen atoms per molecule, 30 parts of white carbon, 0.2 part of a platinum-based catalyst, 0.03 part of an inhibitor, 600 parts of a silver-plated glass conductive filler, and 25 parts of a diluent.

The test results are shown in the following table.

	Dustproof and waterproof	Viscosity (Pa. s)	Volume resistivity (omega cm)
				A	IP67	3100	0.08
II	IP67	2800	0.01
				III	IP67	2900	0.008
Fourthly	IP67	2700	0.10
				Five of them	IP67	3500	0.005

A forming method of a composite part with an IP sealing function and an EMI function comprises the following steps of splitting a product, firstly molding a part of the structure of the product, namely, firstly molding and producing an IP part, and then compounding the produced IP part and the EMI part. I.e., the IP portion is placed into another secondary mold or other structural portion of the mold is replaced and co-molded with the EMI portion.

The temperature for molding the composite part is 150 ℃ to 180 ℃, the vulcanizing time after molding is 100 to 200 seconds, and the pressure for molding is 80 DEG C-180kg/cm². After the IP seal is produced, the excess scrap edge is removed and then compounded with the EMI conducting material. And placing the IP sealing piece after edge dismantling into a die compounded with EMI, positioning, and accurately injecting the liquid conductive adhesive into a position corresponding to the IP sealing piece by adopting a mode of self-injection holes in the die after the positioning is finished. Then, the second compression molding is carried out, the vulcanization reaction is carried out for 150 and 300 seconds at the temperature of 100 and 120 ℃, and then the pressure is 50-150kg/cm²Under the process conditions of (3), forming a cured finished product.

The selected material can be liquid glue or solid glue.

The feeding mode of the die can be directly put in corresponding materials or a mode of transferring and injecting the materials is adopted.

In general, during composite molding, the material of the next step is easy to overflow to the produced part of the previous step, which requires that the mold part is firstly contacted with the first part at the position of the joint required in mold design to seal the material of the next step to overflow to the product of the previous step. Generally, the sealing position of the die and the product in the previous step is more than 0.20mm according to the difference of the hardness of the product.

In order to prevent effective glue overflow at the position where the mold is in contact with the product for sealing, when the feeding molding is solidified, the exhaust distance and the exhaust frequency of the machine are reduced as much as possible, and the phenomenon of air pocket can be ensured by adopting a vacuumizing mode.

When several parts are combined and formed, which part is first and which part is last can be determined according to the structure of the product, and the order of first inside and then outside can be adopted, if the structure is up and down, the order of first bottom and then top is adopted, and the specific structure is determined according to the structure of the product.

The composite with IP sealing and EMI functions produced by this method was tested with conventional rubber products, and the results are shown in the table below.

As can be seen from the table, the viscosity of the composite part with the IP sealing function and the EMI function is suitable, is 2000-4000 Pa.s, and is suitable for the common-mode molding of complex products, so that the material cost is reduced.

The conductive material has high conductivity with volume resistivity less than or equal to 0.1 omega cm, can be used as an electromagnetic shielding material, is widely applied to electronic equipment such as conductive shells, mobile phones and computers, and has waterproof and dustproof performances at the IP67 level.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The invention is described above with reference to the accompanying drawings, it is obvious that the implementation of the invention is not limited in the above manner, and it is within the scope of the invention to adopt various modifications of the inventive method concept and solution, or to apply the inventive concept and solution directly to other applications without modification.