CN108623921B

CN108623921B - EPDM/PP thermoplastic elastomer material and application thereof

Info

Publication number: CN108623921B
Application number: CN201710153371.7A
Authority: CN
Inventors: 吕鹏飞; 王超; 李洪真; 吴卫东
Original assignee: Sinopec Beijing Research Institute of Chemical Industry; China Petroleum and Chemical Corp
Current assignee: Sinopec Beijing Research Institute of Chemical Industry; China Petroleum and Chemical Corp
Priority date: 2017-03-15
Filing date: 2017-03-15
Publication date: 2021-08-03
Anticipated expiration: 2037-03-15
Also published as: CN108623921A

Abstract

The invention relates to the technical field of thermoplastic elastomer material production, and discloses an EPDM/PP thermoplastic elastomer material and application thereof. The EPDM/PP thermoplastic elastomer material with excellent tensile strength can be obtained on the premise of using a small amount of halogen-free flame retardant, and meanwhile, the EPDM/PP thermoplastic elastomer material has good flame retardant property.

Description

EPDM/PP thermoplastic elastomer material and application thereof

Technical Field

The invention relates to the technical field of thermoplastic elastomer material production, in particular to an EPDM/PP thermoplastic elastomer material and application thereof.

Background

The EPDM/PP thermoplastic elastomer material is a thermoplastic elastomer which is firstly brought to the market, has good physical properties, can be processed by adopting thermoplastic plastic processing equipment and technology, and can be widely applied to industries such as household appliances, wires and cables, buildings, automobiles and the like. With the continuous expansion of the application range of EPDM/PP thermoplastic elastomer materials, EPDM/PP TPV gradually replaces the traditional rubber as the third-generation rubber, but the application range is limited because the EPDM/PP TPV is inflammable and emits a large amount of smoke.

At present, two main flame-retardant elastomer materials are available in the market, and one is a flame-retardant elastomer material made of a halogen-containing flame-retardant system; the other is a halogen-free flame-retardant elastomer material made of an inorganic filling flame-retardant system. The two materials have the defects that the halogen-containing flame retardant system is limited by the use of environmental protection organizations such as European Union, thereby greatly limiting the use amount of the halogen-containing flame retardant system; the inorganic filling halogen-free flame retardant system needs to be filled with a large amount of inorganic flame retardant, the mechanical property of the flame retardant elastomer material is obviously reduced, the problem of precipitation exists, and the application and popularization are also greatly limited.

The document (Liu Cuina, etc., the performance research of halogen-free flame retardant EPDM/PP TPV composite materials; the rubber industry, 2009, 5 th stage: 261-265) reports that aluminum hydroxide and magnesium hydroxide are compounded with microcapsule red phosphorus, and resin is added to prepare the flame retardant EPDM/PP TPV composite material, wherein the flame retardant grade can reach UL94V-0(3.2mm) when the addition amount of the flame retardant is 70 parts, but the tensile strength is only 5.95MPa, and the flame retardant is greatly reduced compared with the EPDM/PP TPV composite material without the flame retardant.

CN102786742A discloses a nitrogen-phosphorus system halogen-free flame-retardant TPV material, which is prepared by mixing EPDM, PP, paraffin oil and vulcanizing agent in a mixing roll, and then dynamically vulcanizing in a double-screw extruder to prepare semi-finished particles; and adding SEBS, a nitrogen-phosphorus flame retardant and color master batches into the semi-finished product particles for mixing, and finally granulating by using underwater granulating equipment to obtain the product. The flame retardant rating of the material can reach UL94V-0(3.0mm), but the tensile strength of the material is only 4.5-5.5 MPa.

Disclosure of Invention

The invention aims to overcome the defect of low tensile strength of a TPV material prepared by the prior art and provide an EPDM/PP thermoplastic elastomer material with high tensile strength.

The invention also aims to obtain the EPDM/PP thermoplastic elastomer material with excellent flame retardant performance and mechanical performance in the presence of the halogen-free flame retardant with the least consumption.

In order to achieve the above object, in a first aspect, the present invention provides an EPDM/PP thermoplastic elastomer material, which is composed of a component a and a component B, wherein the component a contains an EPDM rubber, a polypropylene, a softener and a vulcanizing agent, and the component B is a DOPO (9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) grafted magnesium hydroxide composite halogen-free flame retardant.

In a second aspect, the present invention provides the use of the aforementioned EPDM/PP thermoplastic elastomer material as a rubber material. The EPDM/PP thermoplastic elastomer material provided by the invention has obviously excellent tensile strength, and the dosage of the halogen-free flame retardant for forming the EPDM/PP thermoplastic elastomer material is obviously less than that in the prior art.

In addition, the EPDM/PP thermoplastic elastomer material provided by the invention also has excellent flame retardant property.

The EPDM/PP thermoplastic elastomer material provided by the invention can be used in the fields of automobile glass guide grooves, charging pile wires, door and window sealing strips, cable sheaths and the like.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Detailed Description

The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.

In a first aspect, the invention provides an EPDM/PP thermoplastic elastomer material, which consists of a component A and a component B, wherein the component A contains Ethylene Propylene Diene Monomer (EPDM), polypropylene (PP), a softener and a vulcanizing agent, and the component B is a DOPO grafted magnesium hydroxide composite halogen-free flame retardant (D-MH).

The EPDM/PP thermoplastic elastomer material provided by the invention has excellent tensile strength, and the dosage of the halogen-free flame retardant for forming the EPDM/PP thermoplastic elastomer material is obviously less, so that the production cost can be saved.

The ethylene propylene diene monomer can be various ethylene propylene diene monomers commonly used in the field, for example, the ethylene propylene diene monomer has a vinyl structural unit content of 50-70 wt% and a third monomer content of 4-6 wt% based on the total weight of the ethylene propylene diene monomer; the weight average molecular weight of the ethylene propylene diene monomer is 10-40 ten thousand; the third monomer may be various third monomers commonly used in the art, and for example, may be one or more of 1, 4-hexadiene, dicyclopentadiene (DCPD) and 5-ethylidene-2-norbornene, preferably 5-ethylidene-2-norbornene (ENB).

Preferably, the content of the component B is 10 to 40 parts by weight with respect to 100 parts by weight of the component A; more preferably, the content of the component B is 20 to 30 parts by weight with respect to 100 parts by weight of the component A. The inventors of the present invention have found that the tensile strength of an EPDM/PP thermoplastic elastomer material consisting of component a and component B in an amount of 10 to 40 parts by weight, more preferably 20 to 30 parts by weight, relative to 100 parts by weight of component a, can be significantly more excellent.

In the invention, the DOPO grafted magnesium hydroxide composite halogen-free flame retardant is a grafting reactant and is obtained by grafting an organic phosphorus flame-retardant monomer DOPO to an inorganic flame retardant magnesium hydroxide. The inventor of the invention finds that the organic phosphorus flame-retardant monomer DOPO is grafted to the inorganic flame retardant magnesium hydroxide, so that the synergistic flame-retardant and surface-compatibilization modification of the magnesium hydroxide can be realized simultaneously, namely, the single flame-retardant mode of the magnesium hydroxide is compensated by utilizing the condensed phase flame-retardant mechanism of the organic phosphorus flame retardant DOPO catalyzed to form carbon.

Preferably, in the component A, the content of the polypropylene is 45-80 parts by weight, and more preferably 55-75 parts by weight, relative to 100 parts by weight of the ethylene propylene diene monomer.

Preferably, in the component a, the content of the softener is 80 to 120 parts by weight, more preferably 90 to 110 parts by weight, relative to 100 parts by weight of the ethylene-propylene-diene monomer.

Preferably, in the component A, the content of the vulcanizing agent is 1 to 12 parts by weight, more preferably 3 to 10 parts by weight, relative to 100 parts by weight of the ethylene propylene diene monomer.

According to a first preferred embodiment, in the component a, the polypropylene is contained in an amount of 45 to 80 parts by weight, the softener is contained in an amount of 80 to 120 parts by weight, and the vulcanizing agent is contained in an amount of 1 to 12 parts by weight, relative to 100 parts by weight of the ethylene-propylene-diene monomer.

According to a second preferred embodiment, in the component a, the polypropylene is contained in an amount of 55 to 75 parts by weight, the softener is contained in an amount of 90 to 110 parts by weight, and the vulcanizing agent is contained in an amount of 3 to 10 parts by weight, relative to 100 parts by weight of the ethylene-propylene-diene monomer.

Preferably, the softening agent is selected from at least one of cycloalkyl rubber oil, paraffin-based rubber oil and aromatic-based rubber oil; more preferably, the softening agent is naphthenic oil.

Preferably, the vulcanizing agent is selected from at least one of a peroxide vulcanizing system, a phenolic resin vulcanizing system, an amine vulcanizing system and a sulfur vulcanizing system; more preferably, the vulcanizing agent is a phenolic resin.

Preferably, the component A further contains an antioxidant.

Preferably, the antioxidant is at least one selected from the group consisting of antioxidant T501, antioxidant 1010, antioxidant 626 and antioxidant 1076.

Preferably, the antioxidant is contained in an amount of 0.05 to 10 parts by weight, more preferably 0.5 to 5 parts by weight, relative to 100 parts by weight of the ethylene-propylene-diene monomer rubber.

According to a third preferred embodiment, in the component A, relative to 100 parts by weight of ethylene propylene diene monomer, the content of the polypropylene is 45-80 parts by weight, the content of the softener is 80-120 parts by weight, the content of the vulcanizing agent is 1-12 parts by weight, and the content of the antioxidant is 0.05-10 parts by weight.

According to a fourth preferred embodiment, in the component A, relative to 100 parts by weight of ethylene propylene diene monomer, the content of the polypropylene is 55-75 parts by weight, the content of the softener is 90-110 parts by weight, the content of the vulcanizing agent is 3-10 parts by weight, and the content of the antioxidant is 0.5-5 parts by weight.

According to a fifth preferred embodiment, in the component A, the softener is naphthenic oil, the vulcanizing agent is phenolic resin, and the antioxidant is antioxidant 1010; and the content of the component B is 20 to 30 parts by weight with respect to 100 parts by weight of the component A. The inventors of the present invention have found that the tensile strength of the EPDM/PP thermoplastic elastomer material provided by the fifth preferred embodiment of the present invention is optimal.

Preferably, the DOPO-grafted magnesium hydroxide composite halogen-free flame retardant is obtained by bridging DOPO and a silane coupling agent, and then contacting a product obtained after bridging with magnesium hydroxide in the presence of a solvent.

Preferably, the silane coupling agent is at least one of KH560, KH550, KH570, KH590 and Si-69, more preferably KH 560.

Preferably, the solvent is at least one of ethanol, methanol and water. In particular, the solvent is absolute ethanol.

Preferably, the conditions under which the DOPO is bridged with the silane coupling agent include: the reaction temperature is 80-300 ℃, and the reaction time is 0.5-10 h.

Preferably, the conditions under which the product obtained after the bridging is contacted with magnesium hydroxide include: the reaction temperature is 80-160 ℃, and the reaction time is 0.2-10 h.

Preferably, the weight ratio of the DOPO to the silane coupling agent and the magnesium hydroxide is 1: 0.8-2: 10-60 parts of; more preferably, the DOPO is used in a weight ratio of 1: 1-1.5: 15-40.

Preferably, the grafting rate of the DOPO grafted magnesium hydroxide composite halogen-free flame retardant is 0.5-5%; more preferably 1 to 3%. The inventors of the present invention have found that when a D-MH having a graft ratio of 1 to 3% is used, the EPDM/PP thermoplastic elastomer material thus obtained can be made to have significantly more excellent tensile strength and flame retardant properties.

According to a sixth preferred embodiment, said D-MH of the present invention is prepared by a process comprising the steps of:

1) bridging DOPO and a silane coupling agent to obtain a bridged product;

2) dissolving the bridged product in a solvent;

3) contacting the product obtained in step 2) with magnesium hydroxide;

4) keeping the product obtained in the step 3) at 80-160 ℃ for 0.2-10 h.

The EPDM/PP thermoplastic elastomer material of the present invention can be obtained by extrusion and/or injection moulding.

According to a seventh preferred embodiment, the EPDM/PP thermoplastic elastomer material is prepared by a method comprising the following steps:

mixing the component A forming the EPDM/PP thermoplastic elastomer material in a mixing roll for 10-20min, and then dynamically vulcanizing in a double-screw extruder for 0.5-4min under the conditions that the temperature is 150-; and then adding the component B into the semi-finished product particles for mixing, carrying out blending dispersion in a double-screw extruder for 0.5-5min at the temperature of 150-250 ℃ and the rotation speed of 300-700 r/min, carrying out granulation by an underwater granulator, drying, and packaging the particles into finished products.

In a second aspect, the present invention provides the use of the aforementioned EPDM/PP thermoplastic elastomer material as a rubber material.

Preferably, the EPDM/PP thermoplastic elastomer material can be used in the fields of automobile glass guide grooves, charging pile wires, door and window sealing strips, cable sheaths and the like.

The EPDM/PP thermoplastic elastomer material provided by the invention has good processing performance and mechanical performance, and effectively reduces the addition of a flame retardant, thereby greatly widening the application range of the EPDM/PP thermoplastic elastomer material.

The EPDM/PP thermoplastic elastomer material is preferably applied to the fields of automobiles, household appliances, wires and cables, buildings and the like.

The present invention will be described in detail below by way of examples.

In the following preparation examples, comparative examples and test examples, various raw materials used were commercially available without specific description.

The following grafting ratios were measured by thermogravimetric analysis (TGA).

EPDM (3745P DuPont U.S.)

PP (trademark T30S, Daqing refining company of China oil)

The vulcanizing agent used below is a phenolic resin; the antioxidant is antioxidant 1010; the silane coupling agents are KH560 and KH 570; the softener is naphthenic oil.

The following references are given to 1g per part by weight.

Preparation example 1: preparation of D-MH

10g of DOPO and 10g of silane coupling agent KH560 are subjected to heat preservation at 160 ℃ for 2h for bridging to obtain a bridged product; the bridged product was then dissolved in 100mL of absolute ethanol and 400g of magnesium hydroxide were added thereto, stirred well and kept at 120 ℃ for 2 h.

Obtaining D-MH with grafting rate of 1% for later use.

Preparation example 2: preparation of D-MH

10g of DOPO and 12g of silane coupling agent KH560 are subjected to heat preservation at 180 ℃ for 2h for bridging to obtain a bridged product; the bridged product was then dissolved in 120mL of absolute ethanol and 300g of magnesium hydroxide was added thereto, stirred well and kept at 140 ℃ for 4 h.

D-MH was obtained with a grafting yield of 2% for future use.

Preparation example 3: preparation of D-MH

10g of DOPO and 14g of silane coupling agent KH560 are subjected to heat preservation at 140 ℃ for 4 hours for bridging to obtain a bridged product; the bridged product was then dissolved in 150mL of absolute ethanol and 150g of magnesium hydroxide was added thereto, stirred well and kept at 100 ℃ for 6 h.

D-MH was obtained with a grafting yield of 3% for future use.

Preparation example 4: preparation of D-MH

10g of DOPO and 10g of silane coupling agent KH560 are subjected to heat preservation at 160 ℃ for 2h for bridging to obtain a bridged product; the bridged product was then dissolved in 120mL of absolute ethanol and 100g of magnesium hydroxide was added thereto, stirred well and kept at 120 ℃ for 2 h.

D-MH was obtained with a grafting yield of 3.6% for future use.

Preparation example 5: preparation of D-MH

10g of DOPO and 10g of silane coupling agent KH570 are subjected to heat preservation at 160 ℃ for 2h for bridging to obtain a bridged product; the bridged product was then dissolved in 100mL of absolute ethanol and 400g of magnesium hydroxide were added thereto, stirred well and kept at 120 ℃ for 2 h.

Obtaining D-MH with grafting rate of 1% for later use.

Examples 1 to 9: preparation of the EPDM/PP thermoplastic elastomer Material of the invention

The EPDM/PP thermoplastic elastomer material is prepared according to the types and the using amounts of the substances in the component A and the component B in the table 1, and the specific preparation method comprises the following steps:

mixing the component A in the table 1 in a mixing roll for 15min, and then dynamically vulcanizing in a double-screw extruder for 2min under the conditions that the temperature is 200 ℃ and the speed is 500 r/min to prepare semi-finished product particles; and adding D-MH into the semi-finished particles for mixing, blending and dispersing for 2min in a double-screw extruder at the temperature of 200 ℃ and 500 revolutions per minute, granulating by using an underwater granulator, drying, and packaging the particles into a finished product to obtain the EPDM/PP thermoplastic elastomer product.

Comparative examples 1 to 2: preparation of EPDM/PP thermoplastic elastomer material

Comparative example was conducted by the same production method as in example except that the kind of component B was different, specifically, as shown in Table 1.

The EPDM/PP thermoplastic elastomer material is obtained.

TABLE 1

Test example: the EPDM/PP thermoplastic elastomer materials prepared in the foregoing examples and comparative examples were tested for their properties

(1) Flame retardant rating

The vertical burning time(s) was measured according to the test method of GB/T2408-1996 and the flame retardant rating was determined based on the measured vertical burning time(s), sample size 125mm x 12.5mm x 1.6 mm.

(2) Oxygen index%

The sample sizes were 85mm by 10mm by 3.2mm, as tested in GB/T2406-1993.

(3) Tensile strength

The tensile rate was 500mm/min, as measured by ASTM D412.

The test results are listed in table 2.

TABLE 2

As can be seen from tables 1 and 2, the EPDM/PP thermoplastic elastomer material obtained in the example of the present invention has excellent tensile strength and excellent flame retardant property. Also, the product of comparative example 2 had no flame rating. And the mechanical properties (e.g., tensile strength) of the products of comparative examples 1 and 2 were significantly inferior.

In addition, it can be seen from the results of comparative example 1 and example 4 that, under the same conditions except that the amount of D-MH used is different, the flame retardancy and mechanical properties of the product obtained in example 4 are lower than those of example 1 when the amount of component B is 10 parts by weight with respect to 100 parts by weight of component A.

It can be seen from the comparison of the results of example 2 and example 5 that, under the same conditions except that the amount of D-MH used is different, when the amount of component B is 40 parts by weight, with respect to 100 parts by weight of component A, the mechanical properties of the product obtained in example 5 are lower than those of example 2.

It can be seen from the results of comparative example 3 and example 6 that the mechanical properties of the product obtained in example 6 are significantly lower than those of example 3 when component B is used in an amount of 8 parts by weight, relative to 100 parts by weight of component A, under the same conditions except that the amount of D-MH used is different.

It can be seen from the results of comparing example 1 with example 7 that, under the same conditions except that the amount of D-MH used is different, when component B is used in an amount of 50 parts by weight, with respect to 100 parts by weight of component A, the mechanical properties of the product obtained in example 7 are significantly lower than those of example 1.

It can be seen from the results of comparative example 1 and example 8 that, under the same conditions except that the grafting ratio of D-MH used was different, when the grafting ratio of D-MH was 3.6%, the mechanical properties of the product obtained in example 8 were lower than those of example 1.

As can be seen by comparing the results of example 1 and example 9, the conditions were the same except that the D-MH used in example 9 was derived from the D-MH obtained in preparation example 5, and the silane coupling agent used in the preparation of the D-MH of preparation example 5 was KH 570; while example 1 used D-MH derived from the D-MH obtained in preparation example 1, when the silane coupling agent used in the preparation of the D-MH of preparation example 1 was KH560, the flame retardancy and mechanical properties of the product obtained in example 9 were lower than those of example 1.

The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. An EPDM/PP thermoplastic elastomer material is characterized by comprising a component A and a component B, wherein the component A contains ethylene propylene diene monomer, polypropylene, a softening agent and a vulcanizing agent, and the component B is a DOPO grafted magnesium hydroxide composite halogen-free flame retardant with the grafting rate of 1-3%; the DOPO-grafted magnesium hydroxide composite halogen-free flame retardant is obtained by bridging DOPO and a silane coupling agent, and then contacting a product obtained after bridging with magnesium hydroxide in the presence of a solvent; the content of the component B is 20-30 parts by weight relative to 100 parts by weight of the component A; the vulcanizing agent is at least one selected from a peroxide vulcanizing system, a phenolic resin vulcanizing system, an amine vulcanizing system and a sulfur vulcanizing system;

in the component A, relative to 100 parts by weight of ethylene propylene diene monomer, the content of the polypropylene is 45-80 parts by weight, the content of the softener is 80-120 parts by weight, and the content of the vulcanizing agent is 1-12 parts by weight.

2. The material according to claim 1, wherein in the component a, the polypropylene is contained in an amount of 55 to 75 parts by weight, the softener is contained in an amount of 90 to 110 parts by weight, and the vulcanizing agent is contained in an amount of 3 to 10 parts by weight, relative to 100 parts by weight of the ethylene-propylene-diene rubber.

3. The material according to claim 1 or 2, wherein the softening agent is selected from at least one of a cycloalkyl rubber oil, a paraffin-based rubber oil, and an aromatic-based rubber oil.

4. The material according to claim 1 or 2, wherein the component a further comprises an antioxidant.

5. The material of claim 4, wherein the antioxidant is selected from at least one of antioxidant T501, antioxidant 1010, antioxidant 626, and antioxidant 1076.

6. The material according to claim 4, wherein the antioxidant is contained in an amount of 0.05 to 10 parts by weight per 100 parts by weight of the ethylene-propylene-diene monomer.

7. The material according to claim 4, wherein the antioxidant is contained in an amount of 0.5 to 5 parts by weight relative to 100 parts by weight of the ethylene-propylene-diene monomer rubber.

8. The material of claim 1, wherein the silane coupling agent is at least one of KH560, KH550, KH570, KH590, and Si-69.

9. The material of claim 8, wherein the silane coupling agent is KH 560.

10. The material of claim 1, wherein the solvent is at least one of ethanol, methanol, and water.

11. The material of claim 1, wherein the conditions under which DOPO is bridged with a silane coupling agent comprise: the reaction temperature is 80-300 ℃, and the reaction time is 0.5-10 h.

12. The material of claim 1, wherein the conditions under which the product obtained after the bridging is contacted with magnesium hydroxide comprise: the reaction temperature is 80-160 ℃, and the reaction time is 0.2-10 h.

13. The material of claim 1, wherein the DOPO is used in a weight ratio to the silane coupling agent and the magnesium hydroxide of 1: 0.8-2: 10-60.

14. The material of claim 1, wherein the DOPO is used in a weight ratio to the silane coupling agent and the magnesium hydroxide of 1: 1-1.5: 15-40.

15. Use of an EPDM/PP thermoplastic elastomer material as defined in any one of claims 1-14 as a rubber material.