阅读说明：本技术 一种改性硅藻土协效阻燃聚烯烃材料及其制备方法 (Modified diatomite synergistic flame-retardant polyolefin material and preparation method thereof ) 是由 王成 陈静 于 2020-04-26 设计创作，主要内容包括：本发明公开了一种改性硅藻土协效阻燃聚烯烃材料及其制备方法,其中一种改性硅藻土协效阻燃聚烯烃材料,按质量份由以下组分组成：聚烯烃100份,马来酸酐接枝聚乙烯5～10份,氮磷阻燃剂40～60份,改性硅藻土5～10份,抗氧剂1010 0.1～0.5份,硅酮母料6～10份,所述改性硅藻土是将利用苯酚和甲醛制得的酚醛树脂预聚物与硅藻土高速搅拌制得。通过对硅藻土进行表面改性,以消除其表面高能势,调节其疏水性,改善其与有机树脂的润湿性和结合力。将改性硅藻土添加在阻燃聚烯烃材料中,在使材料具有良好阻燃效果的同时使材料具有优异的物理机械性能和低的发烟量,在一定程度上降低了采用氮磷阻燃剂所带来的发烟量大的问题。(The invention discloses a modified diatomite synergistic flame-retardant polyolefin material and a preparation method thereof, wherein the modified diatomite synergistic flame-retardant polyolefin material comprises the following components in parts by mass: 100 parts of polyolefin, 5-10 parts of maleic anhydride grafted polyethylene, 40-60 parts of a nitrogen-phosphorus flame retardant, 5-10 parts of modified diatomite, 10100.1-0.5 part of an antioxidant and 6-10 parts of a silicone master batch, wherein the modified diatomite is prepared by stirring a phenolic resin prepolymer prepared from phenol and formaldehyde and diatomite at a high speed. The surface modification is carried out on the diatomite to eliminate the surface high energy potential, adjust the hydrophobicity and improve the wettability and the bonding force of the diatomite with the organic resin. The modified diatomite is added into the flame-retardant polyolefin material, so that the material has excellent physical and mechanical properties and low smoke generation amount while having good flame-retardant effect, and the problem of large smoke generation amount caused by adopting a nitrogen-phosphorus flame retardant is reduced to a certain extent.)

1. The preparation method of the modified diatomite is characterized by comprising the following steps:

the method comprises the following steps: adding phenol and formaldehyde into a reactor, adding a catalyst, and stirring at 65-80 ℃ to obtain a phenolic resin prepolymer;

step two: and adding the diatomite into a high-speed stirrer at the temperature of 125-140 ℃, adding the phenolic resin prepolymer, and continuously stirring to obtain the modified diatomite.

2. The method for preparing modified diatomite as claimed in claim 1, wherein: in the first step, the molar ratio of phenol to formaldehyde is 1: 1.5.

3. the method for preparing modified diatomite as claimed in claim 1, wherein: in the first step, the catalyst is sodium bicarbonate with the mass of 5-8% of phenol.

4. The method for preparing modified diatomite as claimed in claim 1, wherein: in the second step, the adding proportion of the phenolic resin prepolymer is 3-5% of the mass of the diatomite.

5. The synergistic flame-retardant polyolefin material is characterized by comprising the following components in parts by mass: 100 parts of polyolefin, 5-10 parts of maleic anhydride grafted polyethylene, 40-60 parts of a nitrogen-phosphorus flame retardant, 5-10 parts of modified diatomite, 10100.1-0.5 part of an antioxidant and 6-10 parts of a silicone master batch; the modified diatomite is prepared by the preparation method according to any one of claims 1 to 4.

6. The synergistic flame retardant polyolefin material as claimed in claim 5, wherein: the polyolefin is two or more of polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer and ethylene-octene copolymer.

7. The preparation method of the modified diatomite synergistic flame-retardant polyolefin material is characterized by comprising the following steps:

the method comprises the following steps: weighing the raw material components according to the formula proportion;

step two: adding the raw materials into an internal mixer at the temperature of 130-150 ℃ for mixing for 10-15 min, and discharging materials at the rotor speed of 50-60 rpm;

step three: and (4) adding the material obtained in the step two into a double-screw extruder, extruding and granulating at the temperature of 150-170 ℃, and air-cooling to obtain the flame-retardant polyolefin material.

8. The preparation method of the modified diatomite synergistic flame-retardant polyolefin material as claimed in claim 7, wherein the preparation method comprises the following steps: and the material adding sequence in the second step is to sequentially add the weighed polyolefin, the maleic anhydride grafted polyethylene, the silicone master batch, the antioxidant and the modified diatomite, and add the weighed nitrogen-phosphorus flame retardant after the materials are melted.

Technical Field

The invention belongs to the technical field of high polymer materials, and particularly relates to a modified diatomite synergistic flame-retardant polyolefin material and a preparation method thereof.

Background

The common fire retardant for the halogen-free flame-retardant polyolefin material is a nitrogen-phosphorus fire retardant. In order to achieve good flame-retardant effect of polyolefin, a large amount of magnesium hydroxide or aluminum hydroxide is required to be added, which increases the viscosity of the mixture and leads to severe reduction of the physical and mechanical properties of the material. Although the nitrogen-phosphorus flame retardant is small in addition amount and good in flame retardant effect, the smoke generation amount of the material is increased during combustion. The above problems limit the application of halogen-free flame-retardant polyolefin materials to a certain extent. Therefore, it is required to develop a polyolefin material having excellent physical and mechanical properties, excellent flame retardancy and a small amount of smoke generated during combustion.

The diatomite is a siliceous sedimentary rock with biological origin, and the special porous structure of natural diatomite can be observed under a microscope, and the microporous structure is the reason for the characteristic physicochemical properties of the diatomite, so that the diatomite has the characteristics of large porosity, strong absorptivity, stable chemical properties, wear resistance, heat resistance and the like. Diatomaceous earth does not contain harmful chemical substances, and is widely used as functional fillers, catalyst carriers, adsorbents, purifiers, purification materials, asphalt modifiers and other products. On one hand, the diatomite has higher surface energy, is easy to generate agglomeration phenomenon, has poor distribution degree and dispersibility in resin, and influences the flame-retardant synergistic effect, so that the flame-retardant smoke-suppression effect of the material is unstable; on the other hand, the surface of the diatomite is hydrophilic and has poor compatibility with organic resin, so that the mechanical property of the material is greatly reduced.

Disclosure of Invention

The invention aims to provide a modified diatomite synergistic flame-retardant polyolefin material and a preparation method thereof, which are used for carrying out surface modification on diatomite to eliminate the surface high energy potential of the diatomite, adjust the hydrophobicity of the diatomite and improve the wettability and the bonding force of the diatomite and organic resin. The modified diatomite is added into the flame-retardant polyolefin material, so that the material has excellent physical and mechanical properties and low smoke generation amount while having a good flame-retardant effect, the problem of large smoke generation amount caused by adopting a nitrogen-phosphorus flame retardant is reduced to a certain extent, and the modified diatomite is mainly used for the fields of cable insulation, sheaths and other polyolefin materials needing balancing the problems of mechanics, flame retardance and smoke generation amount.

The technical scheme for realizing the purpose of the invention is as follows:

by adopting the technical scheme, the invention has the following beneficial effects:

a preparation method of modified diatomite comprises the following steps:

the method comprises the following steps: adding phenol and formaldehyde into a reactor, adding a catalyst, and stirring at 65-80 ℃ to obtain a phenolic resin prepolymer;

step two: and adding the diatomite into a high-speed stirrer at the temperature of 125-140 ℃, adding the phenolic resin prepolymer, and continuously stirring to obtain the modified diatomite.

Further, in the first step, the molar ratio of phenol to formaldehyde is 1: 1.5.

further, in the first step, sodium bicarbonate with the mass of 5-8% of phenol is adopted as a catalyst.

Further, in the second step, the adding proportion of the phenolic resin prepolymer is 3-5% of the mass of the diatomite.

A synergistic flame-retardant polyolefin material comprises the following components in parts by mass: 100 parts of polyolefin, 5-10 parts of maleic anhydride grafted polyethylene, 40-60 parts of a nitrogen-phosphorus flame retardant, 5-10 parts of modified diatomite, 10100.1-0.5 part of an antioxidant and 6-10 parts of a silicone master batch.

Further, the polyolefin is two or more of polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer and ethylene-octene copolymer.

A preparation method of a modified diatomite synergistic flame-retardant polyolefin material comprises the following steps:

the method comprises the following steps: weighing the raw material components according to the formula proportion;

step two: adding the raw materials into an internal mixer at the temperature of 130 ℃ for mixing for 10min, wherein the rotor speed is 50-60 rpm, and discharging;

step three: and (4) adding the material obtained in the step two into a double-screw extruder, extruding and granulating at the temperature of 150-170 ℃, and air-cooling to obtain the flame-retardant polyolefin material.

And further, the material adding sequence in the second step is to sequentially add the weighed polyolefin, the maleic anhydride grafted polyethylene, the silicone master batch, the antioxidant and the modified diatomite, and add the weighed nitrogen-phosphorus flame retardant after the materials are melted.

By adopting the technical scheme, the invention has the following beneficial effects:

1. according to the invention, phenolic resin is used as a coating material to modify the diatomite, so that the high energy potential of the surface of the diatomite is eliminated, the hydrophobicity of the diatomite is adjusted, and the wettability and the binding force of the diatomite and the organic resin are improved.

2. According to the flame-retardant polyolefin material prepared by the invention, the modified diatomite is added, so that the flame-retardant polyolefin material has excellent physical and mechanical properties and a good flame-retardant effect, and the problem of large smoke generation caused by the adoption of a nitrogen-phosphorus flame retardant is reduced to a certain extent.

Detailed Description

In order to better understand the above technical solutions, the following detailed descriptions will be provided with reference to specific embodiments.

(example 1)

The embodiment is the prior art, and the composition serving as a comparative example comprises the following components in parts by mass: 40 parts of polyethylene, 60 parts of ethylene-vinyl acetate copolymer, 5 parts of maleic anhydride grafted polyethylene, 50 parts of nitrogen-phosphorus flame retardant, 5 parts of unmodified diatomite, 10100.3 parts of antioxidant and 6 parts of silicone master batch.

(example 2)

The modified diatomite synergistic flame-retardant polyolefin material of the embodiment comprises the following components in parts by mass: 40 parts of polyethylene, 60 parts of ethylene-vinyl acetate copolymer, 5 parts of maleic anhydride grafted polyethylene, 50 parts of nitrogen-phosphorus flame retardant, 5 parts of modified diatomite, 10100.3 parts of antioxidant and 6 parts of silicone master batch.

The preparation method of the modified diatomite synergistic flame-retardant polyolefin material comprises the following steps:

the method comprises the following steps: weighing a mixture with a molar ratio of 1: adding 1.5 of phenol and formaldehyde into a reactor, taking a sodium carbonate solution with 5% of the mass of the phenol as a catalyst, and stirring for 2 hours at 65 ℃ to obtain a phenolic resin prepolymer;

step two: weighing a certain amount of diatomite, adding the diatomite into a high-speed stirrer at the temperature of 125 ℃, adding a phenolic resin prepolymer accounting for 5% of the mass of the diatomite obtained in the first step, and continuously stirring for 3 hours to obtain modified diatomite;

step three: weighing the raw material components according to the formula proportion;

step four: sequentially adding weighed polyolefin, maleic anhydride grafted polyethylene, silicone master batch, antioxidant and modified diatomite into an internal mixer at the temperature of 130 ℃, adding weighed nitrogen and phosphorus flame retardant after materials are melted, mixing the raw materials for 10min at the rotor speed of 50rpm, and discharging;

step five: and D, adding the material obtained in the fifth step into a double-screw extruder, extruding and granulating at the temperature of 160 ℃, and air-cooling to obtain the flame-retardant polyolefin material.

In the embodiment, the phenolic resin is used as a coating material to modify the diatomite, so that the high energy potential of the surface of the diatomite is eliminated, the hydrophobicity of the diatomite is adjusted, and the wettability and the bonding force of the diatomite and the organic resin are improved. By adding the modified diatomite, the flame-retardant polyolefin material has excellent physical and mechanical properties and good flame-retardant effect, and the problem of large smoke quantity caused by adopting a nitrogen-phosphorus flame retardant is reduced to a certain extent.

(example 3)

The modified diatomite synergistic flame-retardant polyolefin material of the embodiment comprises the following components in parts by mass: 30 parts of polyethylene, 10 parts of ethylene-octene copolymer, 60 parts of ethylene-vinyl acetate copolymer, 10 parts of maleic anhydride grafted polyethylene, 60 parts of nitrogen-phosphorus flame retardant, 10 parts of modified diatomite, 10100.3 parts of antioxidant and 8 parts of silicone master batch.

(example 4)

The modified diatomite synergistic flame-retardant polyolefin material of the embodiment comprises the following components in parts by mass: 30 parts of polyethylene, 10 parts of ethylene-octene copolymer, 60 parts of ethylene-vinyl acetate copolymer, 8 parts of maleic anhydride grafted polyethylene, 40 parts of nitrogen-phosphorus flame retardant, 8 parts of modified diatomite, 10100.5 parts of antioxidant and 10 parts of silicone master batch.