CN110819121A

CN110819121A - Flame-retardant material containing organic silicon polymer

Info

Publication number: CN110819121A
Application number: CN201911058065.0A
Authority: CN
Inventors: 不公告发明人
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-11-01
Filing date: 2019-11-01
Publication date: 2020-02-21

Abstract

The invention relates to a flame-retardant material of an organic silicon polymer, which comprises the following components: silicone polymers, hypophosphite salts; wherein the organic silicon polymer is an organic silicon polymer containing one or more hydroxyl groups on a main chain; the molar ratio of silicone polymer to hypophosphite is 2:1 to 4:1. When the linear or reticular organic silicon polymer is directly combusted at high temperature, the hypophosphite can form free metal ions to realize instantaneous coupling reaction with functional groups in the organic silicon polymer, so that the linear or reticular organic silicon polymer is formed. The forming process time of the chain or net-shaped high polymer is extremely short; and the flame-retardant coating has the characteristics of uniformity and compactness, can be covered on materials attached to the flame-retardant material to form a firm and compact isolating membrane which is not easy to penetrate at high temperature, and thus has an effective flame-retardant effect.

Description

Flame-retardant material containing organic silicon polymer

Technical Field

The invention belongs to the field of flame-retardant materials, and particularly relates to a flame-retardant material containing amino silicone oil.

Background

In recent decades, electronic and electrical equipment is manufactured by adopting flame-retardant materials in all countries, so that the safety level of the equipment is greatly improved when the equipment is in fire. Since the last 70 years, flame-retardant nylon has become the mainstream of flame-retardant materials and has wide application in the fields of automobile manufacturing, electronics and electrical and the like. Halogen-containing flame-retardant nylon 66 materials have been used in many cases, but halogen-containing flame-retardant materials generate hydrogen halide during combustion, which causes corrosion to circuitry and other metals, and halogen-containing flame-retardant materials generate other toxic gases during combustion, which causes irritation and damage to the respiratory system of the human body. Therefore, research and development are carried out to replace halogen-containing flame retardant materials.

Silicone polymers are common adjuvants for flame retardant systems and are used as flame retardant materials in middle or outer layers of engineering plastics due to their good inertness and dispersibility, as well as processability. When the flame-retardant silicon carbide is burnt in fire, the organic silicon and related compounds or polymers can generate a silicon carbide coking layer and carbide, so that the flame-retardant silicon carbide has the functions of heat insulation and oxygen insulation and inhibits further burning.

The composite flame-retardant material formed by physically compounding the organic silicon polymer with materials such as magnesium hydroxide, zinc borate, red phosphorus and the like has good flame-retardant effect and has better protection effect on the inner layer. However, the organosilicon polymer used as the outer layer of the flame retardant material has the disadvantages that the synergistic effect is still not very obvious after being compounded with other substances, the flame retardant area is not uniform, and flames or high temperature are likely to flow into the inner layer of the flame retardant layer from the weak area without forming a silicon carbide coking layer and carbide, so that the effect of the flame retardant layer is gradually damaged, and the flame retardant effect is greatly reduced. Therefore, it is highly desirable to find a material with good compatibility and fast reactivity with silicone polymers, which can rapidly form a compact and uniform flame-retardant layer structure with silicone polymers under high-temperature combustion.

Disclosure of Invention

Hypophosphite is a flame retardant additive which is researched more in recent years, and the typical product of the hypophosphite is aluminum hypophosphite which has the advantages of good thermal stability, good water resistance, obvious flame retardant effect and the like. Is mainly used for flame retardance of engineering plastics such as ABS, PET and the like, and has good effect.

However, very few flame retardant materials have been reported in which hypophosphite is blended with a silicone polymer. The invention aims to provide a novel flame-retardant layer structure after uniform physical blending of aluminum hypophosphite and an organic silicon polymer, and the novel flame-retardant layer structure is applied to an outer layer structure of a flame-retardant material. It has been surprisingly found that hypophosphite and silicone polymer are compatible, and can be formed into a uniform, light and thin material, which can be used in the outer layer structure of flame retardant materials. Further, when subjected to direct combustion at high temperature, hypophosphite forms free metal ions, and performs instantaneous coupling reaction with functional groups in the silicone polymer, thereby forming a linear or network-shaped silicone polymer. The organic silicon polymer is essentially a metal silicon carbide coking layer, has compact density, heat resistance and good expansibility, and can fully cover the whole flame-retardant material, thereby realizing excellent flame-retardant effect.

The present invention is realized by the following technical means.

A flame retardant material comprising a silicone polymer, comprising the following ingredients:

an organosilicon polymer, a silicone oil,

a hypophosphite salt;

wherein the organic silicon polymer is an organic silicon polymer containing one or more hydroxyl groups on a main chain;

the molar ratio of silicone polymer to hypophosphite is 2:1 to 4:1.

Under the condition of high-temperature combustion, hydroxyl contained in the organic silicon polymer can rapidly generate coupling reaction with metal ions in hypophosphite, so that chain or net-shaped high polymer is generated, and the flame-retardant material coated material, such as engineering plastics, can be completely covered. Therefore, there is a need in flame retardant materials to ensure that a sufficient number of hydroxyl groups in the silicone polymer can undergo a coupling reaction with the hypophosphite salt, and an excess of silicone polymer should generally be allowed. In the coupling process, the more the number of the reacted hydroxyl groups is, the denser the chain or net-shaped high polymer formed by the coupling reaction is, and the better the flame retardant effect is. In general, the participation degree of the coupling reaction of the hydroxyl group contained in the present invention is 95% or more.

Further, the silicone polymer is a block copolymer.

The block copolymer is preferred in the invention, because the block copolymer can better retain the characteristics and regularity of chain segments formed by the repeating units without hydroxyl in the organic silicon polymer, crystal region parts can be formed as much as possible, and thus the flame-retardant material is more compact; if a random copolymer or an alternating copolymer is used, the repeating units containing hydroxyl groups are dispersed in the repeating units containing no hydroxyl groups as "impurities" and the regularity of segments formed by the repeating units containing no hydroxyl groups is impaired, so that the silicone polymer is in an amorphous state and is deficient in properties in terms of hardness and denseness.

Further, the substituents in the silicone polymer are only hydrogen atoms, alkyl groups, hydroxyl groups, or alkylhydroxyl groups.

Further, the alkyl is C1-C3 alkyl, and the alkyl hydroxyl is C1-C3 alkyl hydroxyl.

To further ensure the regularity of the repeating units in the silicone polymer, the alkyl groups on the repeating units must not be too long, with alkyl groups having a carbon atom of 3 or less being preferred.

Further, the silicone polymer has a polymerizability of repeat units without hydroxyl groups of 50 to 200.

Further, the polymerization degree of the repeating unit containing hydroxyl of the organic silicon polymer is 1-10.

Further, the hydroxyl value in the organic silicon polymer is 10-100 mgKOH/g.

Further, the halogen-free flame-retardant nylon 66 material is characterized in that the antioxidant is selected from alkylphenol, thioether or pentaerythritol ester, and the lubricant is selected from calcium stearate, magnesium stearate or barium stearate. The structure of the silicone polymer may be one of the following structures:

the selected organosilicon polymer is a representative organosilicon polymer, and can ensure that enough hydroxyl groups in the chain segment of the organosilicon polymer can react with hypophosphite, and ensure the regularity and compactness of the organosilicon polymer. Silicone polymers having similar characteristics to the structures listed above should also be considered as falling within the scope of the present patent.

Further, the hypophosphite is selected from aluminum hypophosphite, calcium hypophosphite, magnesium hypophosphite, iron hypophosphite, copper hypophosphite, sodium hypophosphite, potassium hypophosphite, barium hypophosphite, or zinc hypophosphite.

The invention has the following beneficial effects:

the invention reports a flame retardant material containing an organic silicon polymer, which comprises the organic silicon polymer and hypophosphite. Wherein the silicone polymer contains one or more hydroxyl groups in the backbone. Under the condition of high-temperature combustion, hypophosphite can be decomposed into metal ions, and the metal ions can rapidly react with hydroxyl groups on the organic silicon polymer to form chain-shaped or net-shaped high polymer. The forming process time of the chain or net-shaped high polymer is extremely short; the flame-retardant material has the characteristics of uniformity and compactness, can be covered on materials attached to the flame-retardant material to form a firm and compact isolating membrane which is not easy to penetrate at high temperature, and can fully cover the whole flame-retardant material, thereby realizing excellent flame-retardant effect.

Detailed Description

Example 1

aluminum hypophosphite;

wherein the molar ratio of the organosilicon polymer to the aluminum hypophosphite is 2:1.

The preparation method of the flame retardant material containing the organic silicon polymer comprises the following steps:

the organic silicon polymer is put into a reaction container and heated at the temperature of 200 ℃ to enable the organic silicon polymer to present good viscoelasticity, then the aluminum hypochlorite is added into the organic silicon polymer according to the proportion and stirred uniformly, so that the aluminum hypochlorite as a disperse phase is uniformly dispersed in a continuous phase of the organic silicon polymer as much as possible. And then molding, extruding and cooling to obtain the flame-retardant material. The flame-retardant material is generally used as an outer layer of engineering plastics and is coated outside the engineering plastics to play a flame-retardant role.

Example 2

ferric hypophosphite;

wherein the molar ratio of the organic silicon polymer to the ferric hypophosphite is 4:1.

the organic silicon polymer is put into a reaction container and heated at the temperature of 220 ℃ to enable the organic silicon polymer to present good viscoelasticity, then the ferric hypochlorite is added into the organic silicon polymer according to the proportion and stirred uniformly, so that the ferric hypochlorite as a disperse phase is uniformly dispersed in a continuous phase of the organic silicon polymer as much as possible. And then molding, extruding and cooling to obtain the flame-retardant material. The flame-retardant material is generally used as an outer layer of engineering plastics and is coated outside the engineering plastics to play a flame-retardant role.

Example 3

magnesium hypophosphite;

wherein the molar ratio of the organosilicon polymer to the magnesium hypophosphite is 3:1.

the preparation method comprises the steps of putting an organic silicon polymer into a reaction container, heating at 210 ℃ to enable the organic silicon polymer to have good viscoelasticity, then adding magnesium hypochlorite into the organic silicon polymer according to the proportion, and stirring uniformly to enable the magnesium hypochlorite to be used as a disperse phase to be uniformly dispersed in a continuous phase of the organic silicon polymer as much as possible. And then molding, extruding and cooling to obtain the flame-retardant material. The flame-retardant material is generally used as an outer layer of engineering plastics and is coated outside the engineering plastics to play a flame-retardant role.

Example 4

The flame-retardant materials obtained in examples 1 to 3 were used for the flame-retardant test, while the commercially available flame-retardant materials were selected as controls: control 1 is SABIC

PBT-30GF, reference 2, BASF

The blank is selected from a flame-retardant material (molar ratio is 1:1) prepared by blending an organic silicon polymer without any hydroxyl structure in the main chain and aluminum hypophosphite, and the preparation method is the same as that of example 1.

The test for flame retardant properties included: the Limiting Oxygen Index (LOI) test is carried out according to GB/T2406-80, and the sample size is 130mm multiplied by 6.5mm multiplied by 3 mm; UL-94 vertical burning ratings were tested according to GB2409-1996 with sample sizes of 130mm by 6.5mm by 3 mm.

The results obtained are shown in table 1.

Table 1 test data for flame retardant materials

	LOI value (%)	UL-94 vertical burning rating
			Example 1	27.8	V-0
Example 2	28.1	V-0
			Example 3	26.3	V-0
Control 1	25.4	V-0
			Control 2	25.8	V-1
Blank sample	21.3	V-2

As can be seen from the above table, examples 1-3 exhibited excellent flame retardant properties in comparison of the three sets of data for the examples and the controls and blanks, as evidenced by LOI values comparable to, or even slightly better than, the values for controls 1 and 2; and the UL-94 vertical burn rating is also the highest V-0. However, the blank had a larger difference between the LOI value and the UL-94 vertical burning rating than those of examples 1-3, which confirms that aluminum hypophosphite cannot be used as a highly efficient flame retardant material because aluminum hypophosphite cannot chemically react with a silicone polymer containing no hydroxyl group to form a chain or network-like high polymer under high-temperature burning conditions.

Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention and do not limit the protection scope of the present invention. It will be understood by those skilled in the art that various deductions and equivalents may be made to the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A flame retardant material containing a silicone polymer, characterized by comprising the following components:

an organosilicon polymer, a silicone oil,

a hypophosphite salt;

the molar ratio of silicone polymer to hypophosphite is 2:1 to 4:1.

2. The flame retardant silicone polymer-containing material according to claim 1, wherein said silicone polymer is a block copolymer.

3. The flame retardant material of claim 1, wherein the substituents in the silicone polymer are hydrogen atoms, alkyl groups, hydroxyl groups, or alkylhydroxyl groups.

4. The flame retardant silicone polymer-containing material of claim 3, wherein said alkyl group is a C1-C3 alkyl group, and said alkylhydroxy group is a C1-C3 alkylhydroxy group.

5. The flame retardant material of claim 1, wherein the silicone polymer has a polymerizability of repeating units having no hydroxyl group of 50 to 200.

6. The flame retardant material of claim 1, wherein the polymerization degree of the repeating unit of the silicone polymer having a hydroxyl group is 1 to 10.

7. The flame retardant material comprising a silicone polymer according to claim 1, wherein the hydroxyl value in the silicone polymer is from 10 to 100 mgKOH/g.

8. The flame retardant material of claim 1, wherein the silicone polymer has a structure selected from the group consisting of:

9. the flame retardant material comprising an organosilicon polymer, according to claim 1, wherein the hypophosphite is selected from aluminum hypophosphite, calcium hypophosphite, magnesium hypophosphite, iron hypophosphite, copper hypophosphite, sodium hypophosphite, potassium hypophosphite, barium hypophosphite, or zinc hypophosphite.