CN112979854A

CN112979854A - Polyolefin elastomer containing siloxane and preparation method and application thereof

Info

Publication number: CN112979854A
Application number: CN202110352244.6A
Authority: CN
Inventors: 牛慧; 孙爽; 庞洪昌
Original assignee: Dalian University of Technology
Current assignee: Dalian University of Technology
Priority date: 2021-03-31
Filing date: 2021-03-31
Publication date: 2021-06-18
Anticipated expiration: 2041-03-31
Also published as: CN112979854B

Abstract

The invention discloses a siloxane-containing polyolefin elastomer and a preparation method and application thereof. The polyolefin elastomer can be prepared from olefin monomers by a copolymerization method, and can also be prepared by a free radical grafting method of polyolefin. The prepared polyolefin elastomer can generate a large amount of silicon dioxide and carbon residue after combustion due to the siloxane component, so that the material has a flame retardant function.

Description

Polyolefin elastomer containing siloxane and preparation method and application thereof

Technical Field

The invention relates to a polyolefin elastomer and a preparation method and application thereof, in particular to a preparation method and application of a polyolefin elastomer with siloxane-containing side groups.

Background

The polyolefin elastomer is a high value-added polyolefin material, has the characteristics of good chemical stability, excellent corrosion resistance, strong electrical insulation, excellent processability and the like of the polyolefin material, has the characteristic of excellent low-temperature performance of rubber, and is widely applied to the fields of wires and cables, building waterproof materials, household appliances, automobile manufacturing, medical treatment and the like. As the polyolefin belongs to flammable materials, huge fire hazard exists in practical application, and the wider application of the polyolefin elastomer is restricted. Therefore, flame retardant properties become one of the important properties of polyolefin elastomers. With the continuous development of society, the safety standard of the manufacturing industry for rubber and plastic products is gradually improved, and the efficient flame-retardant modification of polyolefin elastomers is urgent. Most of the flame retardants added to the early elastomer products are halogen flame retardants, but the decomposition products of the halogen flame retardants after combustion contain many harmful substances, and the application thereof is gradually limited. At present, the flame retardant of the elastomer material mainly takes high efficiency, low smoke and no toxicity as the development direction, and the research and application of various halogen-free flame retardants also become the most active research field for flame retardant modification of polyolefin elastomers. For example, phosphorus-based flame retardants can exhibit flame retardant properties in the condensed or gas phase, promote char formation, and insulate the polymer matrix from heat, fire, and oxygen to achieve flame retardant functionality. For another example, the intumescent composite flame retardant generates gaseous water and non-combustible gas during combustion to expand the polymer in a molten state, and meanwhile, the polyol and ester in the flame retardant form inorganic matters and carbon residues during decomposition and carbonization, so that air is blocked and combustion is inhibited. However, at present, the most common halogen-free flame retardant systems are also inorganic metal oxides represented by magnesium hydroxide. The inorganic flame retardant is dispersed in the polyolefin elastomer in a physical mixing mode, and the inorganic flame retardant plays a role in flame retardance in a condensed phase or a gas phase through physical or chemical changes. Besides good combustion inhibition effect, the inorganic flame retardant also has the advantages of low smoke, no toxicity and environmental protection, and is the trend of the development of the flame retardant in the future; the disadvantage is that the inorganic flame retardant usually needs higher addition amount (more than 50%) to achieve better flame retardant effect, which undoubtedly has great influence on the elasticity of the product and is not beneficial to the optimization of the product performance. In addition, the organic silicon flame retardant is also a halogen-free flame retardant, and the flame retardant mechanism of the organic silicon flame retardant is that an inorganic layer of silicon dioxide and carbide can be generated during combustion, so that the organic silicon flame retardant plays a role in blocking air and heat, and thus, the combustion is inhibited. For example, silicone resins and silicone rubbers have excellent flame retardant properties by themselves, but have the disadvantage of being expensive.

Disclosure of Invention

According to the invention, the siloxane chain segment is chemically connected to the polyolefin elastomer side group, so that the polyolefin elastomer substrate is endowed with a flame-retardant function, and the application of the siloxane chain segment in the field of flame-retardant materials is greatly widened.

The invention provides a polyolefin elastomer with siloxane-containing side groups, which has the following structure:

wherein R is¹Is C₁～C₂₀Linear, branched or isomerized alkyl, or C₆～C₂₀Aryl of (A), R²Is H or CH₃R3 is C₁～C₁₂The straight-chain alkane of (1); x is 100-100000, preferably x is 500-50000; y is 100-50000, preferably y is 500-20000; z is 0.0001x to 0.2x, preferably 0.001x to 0.1 x; m is a positive integer of 1 to 3, and n is a positive integer of 1 to 100.

Another object of the present invention is to provide a method for preparing the above polyolefin elastomer, comprising the steps of:

copolymerizing ethylene and alpha-olefin (I) and alpha-olefin (II) having the following structures in the presence of a catalyst to obtain a silicone-containing polyolefin elastomer;

α -olefin (I):

CH₂＝CH-R³

α -olefin (II):

wherein R is¹Is C₁～C₂₀Linear, branched or isomerized alkanes ofRadical, or C₆～C₂₀Or R is an aromatic radical of¹Absent, with silicon atoms directly attached to carbon atoms in ethylene, preferably R¹Is C₂～C₈A straight-chain alkyl group of (A), or C₆～C₁₄An aromatic group of (a); r²Is H or CH₃；R³Is C₁～C₁₂Linear alkanes of (1), preferably R³Is C₁～C₈The straight-chain alkane of (1); m is a positive integer of 1-3, preferably m is 2 or 3; n is a positive integer of 1 to 100, preferably 1 to 20.

Further, the catalyst comprises a Ziegler-Natta catalyst or a metallocene catalyst.

Further, when the polyolefin elastomer of the present invention is prepared by the above polymerization method, the α -olefin (I) is used in an amount of 1 to 500 parts by mole, preferably 20 to 200 parts by mole, relative to 100 parts by mole of the ethylene monomer; the amount of the alpha-olefin (II) is 0.01 to 50 parts by mole, preferably 0.1 to 20 parts by mole. The polymerization conditions include: the polymerization pressure is 0.1-6 MPa, preferably 0.1-4 MPa; the polymerization temperature is 30-150 ℃, preferably 60-120 ℃; the polymerization time is 0.1 to 6 hours, preferably 0.2 to 3 hours.

The preparation method of the polyolefin elastomer can also be prepared by the following steps: the method comprises the following steps:

carrying out copolymerization reaction on ethylene and alpha-olefin (I) with the structure in the presence of a catalyst to obtain an ethylene/alpha-olefin (I) copolymer;

obtaining a siloxane-containing polyolefin elastomer by performing free radical grafting reaction on an ethylene/alpha-olefin (I) copolymer and alpha-olefin (III) with the following structure under the action of an initiator;

α -olefin (I):

CH₂＝CH-R³

α -olefin (III):

wherein R is^1’Is C₆～C₂₀Aryl or R of^1’Absent, with silicon atoms directly bound to carbon atoms in ethylene, R²Is H or CH₃，R³Is C₁～C₁₂The straight-chain alkane of (1); preferably R^1’Is C₆～C₁₄Further preferably R^1’Is C₆Aryl or R^1’Absent, with silicon atoms directly bound to carbon atoms in ethylene, R²Is H or CH₃，R³Is C₁～C₈The straight-chain alkane of (1); m is a positive integer of 1-3, preferably m is 2 or 3; n is a positive integer of 1 to 100, preferably 1 to 20.

Further, the initiator includes an organic peroxide-based initiator or an azo-based initiator.

Further, the organic or oxide type initiator includes dicumyl peroxide; the azo initiator includes 2, 5-dimethyl-2, 5-di (t-butylperoxy) hexane.

Further, when the polyolefin elastomer of the present invention is produced by the above-mentioned radical grafting method, the α -olefin (III) is used in an amount of 0.1 to 100 parts by mass, preferably 1 to 50 parts by mass, relative to 100 parts by mass of the ethylene/α -olefin (I) copolymer; the amount of the initiator is 0.01 to 1 part by mass, preferably 0.05 to 0.5 part by mass. The conditions of the radical grafting method include: the raw materials are mixed and then added into reactive processing equipment, and the processing temperature is 120-250 ℃, preferably 150-210 ℃. The reactive processing equipment comprises one of a single-screw extruder, a double-screw extruder, an open mill and an internal mixer.

The invention also provides the application of the siloxane-containing polyolefin elastomer as a raw material of the flame-retardant polyolefin elastomer.

The invention not only can solve the problem of poor compatibility between the added flame retardant and the polyolefin elastomer, but also can ensure the good flexibility of the polyolefin elastomer; the siloxane component of the polymer side group can play a role of a silicon flame retardant when the polyolefin elastomer is burnt, and the optimized flame retardant function of the polyolefin elastomer is endowed by generating a silicon dioxide inorganic layer and a carbide in situ during the burning.

Drawings

FIG. 1 is a photograph of the experimental residue of thermogravimetric analysis of a sample of example 3 (nitrogen experimental atmosphere).

FIG. 2 is a photograph of the experimental residue of the thermogravimetric analysis of the sample of example 3 (air experimental atmosphere).

FIG. 3 is a graph of the thermal weight loss of a polyolefin elastomer.

Detailed Description

The following examples are presented as further illustrations and are not intended to limit the scope of the claims. The alpha-olefins having the formula A, B, C used in the examples of the present invention were obtained by the following routes or manners.

For the synthesized alpha-olefin monomer, the application provides a conventional synthesis method, and the alpha-olefin monomer is not limited.

(1) α -olefin monomer a:

adding 3.5g of magnesium chips and 0.8g of 6-bromo-1-hexene into a 500mL three-neck flask, adding 200mL of dried tetrahydrofuran into the flask under the nitrogen atmosphere, starting stirring, adding 50mg of iodine into the reaction solution, stirring for 30min at room temperature, then slowly dropwise adding 25.3g of 6-bromo-1-hexene, and carrying out reflux reaction for 6 hours until the solid in the reaction flask disappears. Filtering under the protection of nitrogen, and collecting filtrate to obtain 5-hexenyl magnesium bromide solution.

Adding 100mL of dry tetrahydrofuran into a 500mL three-neck flask, weighing 12.1g of methyltrichlorosilane into the flask under the nitrogen atmosphere, starting stirring, slowly dropwise adding the 5-hexenyl magnesium bromide solution prepared in the previous step into the flask, stirring at room temperature for reaction for 12 hours, and carrying out reduced pressure distillation and refining to obtain the 5-hexenyl methyl dichlorosilane.

Dissolving an excessive amount of 5-methoxy-1, 1,3,3,5, 5-hexamethyl-1-hydroxytrisiloxane (CAS No.49778-22-5) in 100mL of anhydrous tetrahydrofuran, slowly dripping the dissolved 5-hexenylmethyl-dichlorosilane into the anhydrous tetrahydrofuran, reacting at 0 ℃ for 24 hours, distilling the tetrahydrofuran and excessive unreacted reactants under reduced pressure, and obtaining the alpha-olefin monomer A at the bottom of a reaction bottle. The structural formula is as follows:

(2) α -olefin monomer B:

after 5g of magnesium chips and 100mL of anhydrous tetrahydrofuran were put into a 250mL three-necked flask, 10g of 4-chlorostyrene was added dropwise thereto, and the reaction was carried out for 2 hours, the resulting suspension was transferred to a constant pressure dropping funnel, and the suspension was added dropwise to a three-necked flask containing 50mL of anhydrous tetrahydrofuran and 11.56g of methyltrichlorosilane and reacted at room temperature for 20 hours. And (3) distilling under reduced pressure to remove tetrahydrofuran, filtering to obtain a crude product, continuing distilling under reduced pressure, and collecting fractions at 40-60 ℃.1mol of the collected product is taken and dissolved in 100mL of anhydrous tetrahydrofuran, slowly dropped into 2mol of hexamethyl-1, 5-dihydroxy trisiloxane (CAS No.3663-50-1), reacted for 24 hours at 0 ℃, and then the tetrahydrofuran is removed by reduced pressure distillation to obtain the alpha-olefin monomer B. The structural formula is as follows:

(3) α -olefin monomer C:

after 5g of magnesium chips and 100mL of anhydrous tetrahydrofuran were put into a 250mL three-necked flask, 10g of 4-chlorostyrene was added dropwise thereto, and the mixture was reacted for 2 hours, the resulting suspension was transferred to a constant pressure dropping funnel, and the mixture was added dropwise to a three-necked flask containing 50mL of anhydrous tetrahydrofuran and 12.7g of tetrachlorosilane and reacted for 20 hours at room temperature. And (3) distilling under reduced pressure to remove tetrahydrofuran, filtering to obtain a crude product, continuing distilling under reduced pressure, and collecting fractions at 40-60 ℃.1mol of the collected product is taken and dissolved in 100mL of anhydrous tetrahydrofuran, slowly dropped into 3mol of 1,1,3, 3-tetramethyl-1, 3-disiloxane diol (CAS No.1118-15-6) to react for 24 hours at 0 ℃, and the tetrahydrofuran is removed by reduced pressure distillation to obtain the alpha-olefin monomer C. The structural formula is as follows:

comparative example 1

In a 500mL reactor with mechanical stirring, 100mL of toluene, 4mmol of methylaluminoxane and 2. mu. mol of metallocene catalyst C were added₂H₄(Ind)₂ZrCl₂An ethylene/propylene mixed gas (0.5 MPa) was introduced thereinto, wherein the ratio of ethylene to propylene was 1: 1(v/v), and the reaction was carried out at 60 ℃ for 1 hour. The polymerization product was collected, washed and dried to obtain 28.5g of an ethylene-propylene copolymer.

The ethylene content of the polymer was 59.7 mol% and the propylene content was 40.3 mol%. The basic polymer properties are shown in Table 1.

Comparative example 2

In a 500mL reactor with mechanical stirring, 100mL of toluene, 20mL of 1-octene, 4mmol of methylaluminoxane and 2. mu. mol of metallocene catalyst C were added₂H₄(Ind)₂ZrCl₂And introducing ethylene under 0.3MPa to react at 60 ℃ for 0.5 hour. The polymerization product was collected, washed and dried to obtain 15.0g of an ethylene/1-octene copolymer.

The ethylene content of the polymer was 75.5 mol%, and the 1-octene content was 24.5 mol%. The basic polymer properties are shown in Table 1.

Example 1

In a 500mL reactor with mechanical stirring, 100mL of toluene, 12g of alpha-olefin monomer A, 4mmol of methylaluminoxane and 2. mu. mol of metallocene catalyst C were added₂H₄(Ind)₂ZrCl₂An ethylene/propylene mixed gas (0.5 MPa) was introduced thereinto, wherein the ratio of ethylene to propylene was 1: 1(v/v), and the reaction was carried out at 60 ℃ for 1 hour. The polymerization product was collected, washed and dried to obtain 17.6g of a silicone-containing polyolefin elastomer.

The polymer had an ethylene content of 55.2 mol%, a propylene content of 38.7 mol% and an alpha-olefin monomer A content of 6.1 mol%. The basic polymer properties are shown in Table 1.

Example 2

In a 500mL reactor with mechanical stirring, 100mL of toluene, 20mL of 1-octene, 20g of alpha-olefin monomer A, 10mmol of methylaluminoxane, 4. mu. mol of metallocene catalyst C₂H₄(Ind)₂ZrCl₂And introducing ethylene under 0.3MPa to react at 60 ℃ for 0.5 hour. Collecting the polymerization product, washing and drying to obtain the silicon-containing polymer18.2g of an alkylene oxide polyolefin elastomer.

The polymer had an ethylene content of 65.4 mol%, a 1-octene content of 21.5 mol%, and an alpha-olefin monomer A content of 13.1 mol%. The basic polymer properties are shown in Table 1.

Example 3

In a 500mL reactor with mechanical stirring, 100mL of toluene, 20mL of 1-octene, 10g of alpha-olefin monomer B, 15mmol of methylaluminoxane, 4. mu. mol of metallocene catalyst C₂H₄(Ind)₂ZrCl₂And introducing ethylene under 0.3MPa to react at 60 ℃ for 0.5 hour. The polymerization product was collected, washed and dried to obtain 14.7g of a silicone-containing polyolefin elastomer.

The polymer had an ethylene content of 72.3 mol%, a 1-octene content of 20.9 mol%, and an alpha-olefin monomer B content of 6.8 mol%. The basic polymer properties are shown in Table 1.

Example 4

100 parts by mass of the ethylene-propylene copolymer synthesized in comparative example 1, 0.1 part of 1010 (antioxidant), 0.2 part of 168 (antioxidant), 0.1 part of dicumyl peroxide (initiator), 15 parts of the α -olefin monomer B of the present invention were mixed, and the mixture was then charged into an internal mixer (HAAKE, germany) and processed. The processing temperature is 150 ℃, the set rotating speed is 60rpm, and the processing time is 3min, so that the siloxane-containing polyolefin elastomer product is obtained. The product structure and properties are shown in table 1.

Example 5

100 parts by mass of the ethylene-propylene copolymer synthesized in comparative example 1, 0.1 part of 1010 (antioxidant), 0.2 part of 168 (antioxidant), 0.2 part of dicumyl peroxide (initiator), 30 parts of the α -olefin monomer B of the present invention were mixed, and the mixture was then charged into an internal mixer (HAAKE, germany) and processed. The processing temperature is 150 ℃, the set rotating speed is 60rpm, and the processing time is 4min, so that the siloxane-containing polyolefin elastomer product is obtained. The product structure and properties are shown in table 1.

Example 6

100 parts by mass of the ethylene-propylene copolymer synthesized in comparative example 1, 0.1 part of 1010 (antioxidant), 0.2 part of 168 (antioxidant), 0.15 part of 2, 5-dimethyl-2, 5-di (t-butylperoxy) hexane (initiator), 35 parts of the α -olefin monomer B of the present invention were mixed, and the mixture was then charged into an internal mixer (HAAKE, germany) for processing. The processing temperature is 150 ℃, the set rotating speed is 60rpm, and the processing time is 4min, so that the siloxane-containing polyolefin elastomer product is obtained. The product structure and properties are shown in table 1.

Example 7

100 parts by mass of the ethylene/1-octene copolymer synthesized in comparative example 2, 0.1 part of 1010 (antioxidant), 0.2 part of 168 (antioxidant), 0.15 part of 2, 5-dimethyl-2, 5-di (t-butylperoxy) hexane (initiator), 30 parts of the α -olefin monomer B of the present invention were mixed, and the mixture was then charged into an internal mixer (HAAKE, germany) for processing. The processing temperature is 170 ℃, the set rotating speed is 60rpm, and the processing time is 4min, so that the siloxane-containing polyolefin elastomer product is obtained. The product structure and properties are shown in table 1.

Example 8

100 parts by mass of the ethylene/1-octene copolymer synthesized in comparative example 2, 0.1 part 1010 (antioxidant), 0.2 part 168 (antioxidant), 0.2 part 2, 5-dimethyl-2, 5-di (t-butylperoxy) hexane (initiator), 35 parts of the α -olefin monomer C of the present invention were mixed, and the mixture was then charged into an internal mixer (HAAKE, germany) for processing. The processing temperature is 170 ℃, the set rotating speed is 60rpm, and the processing time is 4min, so that the siloxane-containing polyolefin elastomer product is obtained. The product structure and properties are shown in table 1.

Example 9

100 parts by mass of the ethylene/1-octene copolymer synthesized in comparative example 2, 0.1 part of 1010 (antioxidant), 0.2 part of 168 (antioxidant), 0.1 part of 2, 5-dimethyl-2, 5-di (t-butylperoxy) hexane (initiator), 15 parts of the α -olefin monomer C of the present invention were mixed, and the mixture was then charged into an internal mixer (HAAKE, germany) for processing. The processing temperature is 170 ℃, the set rotating speed is 60rpm, and the processing time is 2min, so that the siloxane-containing polyolefin elastomer product is obtained. The product structure and properties are shown in table 1.

Example 10

100 parts by mass of the ethylene/1-octene copolymer synthesized in comparative example 2 and 100 parts by mass of the silicone-containing polyolefin elastomer synthesized in example 2 were mixed, and the mixture was then charged into an internal mixer (HAAKE, Germany) and processed. The processing temperature is 170 ℃, the set rotating speed is 60rpm, and the processing time is 1min, so that the product is obtained. The product structure and properties are shown in table 1.

TABLE 1 Polymer Structure and Properties

It can be seen that the conventional polyolefins (comparative example 1, comparative example 2) had no flame retardant function and the weight of the residue after the completion of the burning test was 0. The siloxane-containing polyolefin elastomer of the present invention has residues remained after the combustion test is completed, and it can be observed in fig. 1 and 2 that a large amount of residues remained in the sample dish after the thermogravimetric analysis (TGA) test of the siloxane-containing polyolefin elastomer of the present invention (example 3), which indicates that the sample has obvious flame retardant property.

The thermogravimetric analysis of the residual weight percentages for all samples of the inventive examples are listed in table 1. The thermogravimetric curves of comparative example 1, comparative example 2, examples 3, 6, and 9 are shown in FIG. 3. Because the siloxane component is introduced into the polymer, the polymer can not be completely burnt out when subjected to a thermal weight loss test, and a certain proportion of residues (silicon dioxide and carbon residue) are still remained at 700 ℃. With the increase of the content of siloxane, the proportion of residues after the thermal weight loss test is gradually increased, and the flame retardant property is better.

The flame-retardant polyolefin elastomer prepared by the invention can be blended with common polyolefin to endow the common polyolefin with a flame-retardant function, for example, example 10 is obtained by blending the products of example 2 and comparative example 2, and also shows obvious flame-retardant effect. Therefore, the polyolefin elastomer is a novel material with a self-flame-retardant function, and can be used as a flame-retardant material alone or mixed with other materials.

Meanwhile, the obtained polyolefin elastomer keeps the advantage of low glass transition temperature, and because the introduced siloxane component is positioned on the polymer side group and has proper content, the flexibility of the polyolefin elastomer main chain is not obviously influenced, so that the polyolefin elastomer can still keep elasticity at low temperature.

Claims

1. A silicone-containing polyolefin elastomer characterized by the structure:

wherein R is¹Is C₁～C₂₀Linear, branched or isomerized alkyl, or C₆～C₂₀Aryl of (A), R²Is H or CH₃，R³Is C₁～C₁₂The straight-chain alkane of (1); x is 100-100000, y is 100-50000, and z is 0.0001-0.2 x; m is a positive integer of 1 to 3, and n is a positive integer of 1 to 100.

2. A process for preparing a polyolefin elastomer as claimed in claim 1, characterized in that it comprises the following steps: copolymerizing ethylene and alpha-olefin (I) and alpha-olefin (II) having the following structures in the presence of a catalyst to obtain a silicone-containing polyolefin elastomer;

α -olefin (I):

CH₂＝CH-R³

α -olefin (II):

in the formula, R¹Is C₁～C₂₀Linear, branched or isomerized alkyl, or C₆～C₂₀Or R is an aromatic radical of¹Absent, with silicon atoms directly bound to carbon atoms in ethylene, R²Is H or CH₃，R³Is C₁～C₁₂The straight-chain alkane of (1); m is a positive integer of 1 to 3, n is1 to 100 positive integers.

3. The method of claim 2, wherein R is¹Is C₂～C₈A straight-chain alkyl group of (A), or C₆～C₁₄Or R is an aromatic radical of¹Absent, the silicon atom is directly attached to a carbon atom in ethylene; r²Is H or CH₃，R³Is C₁～C₈The straight-chain alkane of (1); m is 2 or 3, and n is a positive integer of 1-20.

4. The method of claim 2, wherein the catalyst comprises a Ziegler-Natta catalyst or a metallocene catalyst.

5. The production method according to claim 2, wherein the α -olefin (I) is used in an amount of 1 to 500 parts by mole relative to 100 parts by mole of the ethylene monomer; the dosage of the alpha-olefin (II) is 0.01-50 molar parts; the polymerization conditions include: the polymerization pressure is 0.1-6 MPa, the polymerization temperature is 30-150 ℃, and the polymerization time is 0.1-6 hours.

6. A process for preparing a polyolefin elastomer as claimed in claim 1, characterized in that it comprises the following steps: carrying out copolymerization reaction on ethylene and alpha-olefin (I) with the structure in the presence of a catalyst to obtain an ethylene/alpha-olefin (I) copolymer;

α -olefin (I):

CH₂＝CH-R³

α -olefin (III):

in the formula (I), the compound is shown in the specification,R^1’is C₆～C₂₀Aryl or R of^1’Absent, with silicon atoms directly bound to carbon atoms in ethylene, R²Is H or CH₃，R³Is C₁～C₁₂The straight-chain alkane of (1); m is a positive integer of 1 to 3, and n is a positive integer of 1 to 100.

7. The method of claim 6, wherein R is^1’Is C₆～C₁₄An aromatic group of (a); r²Is H or CH₃，R³Is C₁～C₈The straight-chain alkane of (1); m is 2 or 3, and n is a positive integer of 1-20.

8. The method according to claim 6, wherein the initiator comprises an organic peroxide initiator or an azo initiator.

9. The production method according to claim 6, wherein the α -olefin (III) is used in an amount of 0.1 to 100 parts by mass relative to 100 parts by mass of the ethylene/α -olefin (I) copolymer; the amount of the initiator is 0.01-1 part by mass; the conditions of the radical grafting reaction include: mixing the raw materials, and adding the mixture into reactive processing equipment, wherein the processing temperature is 120-250 ℃; the reactive processing equipment comprises one of a single-screw extruder, a double-screw extruder, an open mill and an internal mixer.

10. Use of the silicone-containing polyolefin elastomer of claim 1 as a raw material for flame-retardant polyolefin elastomers.