CN104327511A - Low-smoke halogen-free flame retardant composition for silicone rubber and application thereof - Google Patents
Low-smoke halogen-free flame retardant composition for silicone rubber and application thereof Download PDFInfo
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- CN104327511A CN104327511A CN201410598587.0A CN201410598587A CN104327511A CN 104327511 A CN104327511 A CN 104327511A CN 201410598587 A CN201410598587 A CN 201410598587A CN 104327511 A CN104327511 A CN 104327511A
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Abstract
The invention provides a low-smoke halogen-free flame retardant composition for silicone rubber and application thereof. The low-smoke halogen-free flame retardant composition for silicone rubber comprises melamine urate, aluminum hydroxide, ammonium polyphosphate and pentaerythritol. A silicone rubber product added with the low-smoke halogen-free flame retardant composition not only has excellent flame retardant property, but also has excellent physical and mechanical properties and processability. The flame retardant composition is of a low-smoke and halogen-free type and is non-poisonous, odorless and friendly to the environment.
Description
Technical field
The invention belongs to silicon rubber flame retardant area, be specifically related to a kind of silicon rubber low-smoke non-halogen flame-retardant agent composition and application thereof.
Technical background
Silicon rubber is a kind of special synthetic rubber, different from the C-C key main chain of most of rubber, the main chain of silicon rubber is Si-O bond structure, and the singularity of silastic structure makes silicon rubber have excellent high temperature resistant, low temperature resistant, high pressure resistant, ageing-resistant, electric insulating quality and resistance to electric leakage performance.At present, silicon rubber is used widely in defence and military, industrial and agricultural production, health care and people's daily life, becomes one of kind with fastest developing speed in novel material.Along with the development of rubber industry and the raising of industrialized level, people are also more and more higher for the requirement of Silicone Rubber, especially flame retardant properties.
At present, the halogen-free flame retardants for silicon rubber mainly contains metal hydroxides (magnesium hydroxide, aluminium hydroxide), zinc borate, trimeric cyanamide and contains platinic compound etc.Although metal hydroxides inorganic combustion inhibitor has good fire-retardant and environmental-protecting performance, need a large amount of filling just can reach flame-retardancy requirements, to the processing characteristics of silicon rubber and physicals infringement larger.Although excellent containing platinic compound flame retardant effect, it is expensive and have certain toxicity, and in use procedure, vulnerable to pollution causes flame retardant properties unstable.Trimeric cyanamide has good flame retardant effect to silicon rubber, but temperature tolerance is poor, affects the resistance toheat of silicon rubber.Although bromide fire retardant good flame retardation effect, addition are low, toxicant can be produced under high temperature and combustion conditions.Therefore, urgently work out a kind of environmental friendliness, LSZH, cheap, and prejudicial fire retardant is not had to the processing characteristics of silicon rubber and physicals.
Summary of the invention
The present invention aims to provide a kind of silicon rubber low-smoke non-halogen flame-retardant agent composition and application thereof, this low-smoke non-halogen flame-retardant agent composition environmental protection, excellent fireproof performance and LSZH, add in silicon rubber base material, the silastic product of preparation is while the flame retardant properties keeping excellence, good mechanical property can be had, processing characteristics and resistance toheat.
The technical solution adopted in the present invention is:
A kind of silicon rubber low-smoke non-halogen flame-retardant agent composition, is characterized in that, composed of the following components: modified melamine cyanurate, aluminium hydroxide, ammonium polyphosphate and tetramethylolmethane,
Wherein, the weight ratio of melamine cyanurate, aluminium hydroxide, ammonium polyphosphate and tetramethylolmethane is 1 ~ 15:5 ~ 20:15 ~ 30:1 ~ 10.
Preferably, the weight ratio of described melamine cyanurate, aluminium hydroxide, ammonium polyphosphate and tetramethylolmethane is 5 ~ 10:10 ~ 15:15 ~ 20:1 ~ 3.
Preferably, described melamine cyanurate is modified melamine cyanurate.
Preferably, the properties-correcting agent of described modified melamine cyanurate is silane coupling agent, melamine cyanurate and properties-correcting agent mix and blend is obtained; Wherein weight proportion shared by properties-correcting agent is 1% ~ 3% of melamine cyanurate.
Described modified melamine cyanurate can also be selected from the commercially available prod of Jinan Taixing Fine Chemicals Co., ltd.
Preferably, described aluminium hydroxide particle size range is 0.8 ~ 2 μm;
Described ammonium polyphosphate is crystal II-type ammonium polyphosphate, and its polymerization degree is greater than 1000.
The invention also discloses a kind of low-smoke non-halogen flame-retardant silicon rubber being added with above-mentioned silicon rubber low-smoke non-halogen flame-retardant agent composition, silicon rubber low-smoke non-halogen flame-retardant agent composition is added in described low-smoke non-halogen flame-retardant silicon rubber, the addition of described silicon rubber low-smoke non-halogen flame-retardant agent composition is: with 100 parts of raw-silastic continuouslies for benchmark, be no more than 35 parts;
Described silicon rubber is methyl vinyl silicon kautschuk, and its molecular weight is 50 ~ 700,000, and vinyl molar content is 0.08% ~ 0.16%.
Preferably, be also added with strengthening agent in described low-smoke non-halogen flame-retardant silicon rubber, described strengthening agent is gas-phase silica,
The addition of described strengthening agent is: with 100 parts of raw-silastic continuouslies for benchmark, and strengthening agent consumption is 20 ~ 40 parts.
Preferably, be also added with structurizing treatment agent in described low-smoke non-halogen flame-retardant silicon rubber, described structurizing treatment agent is hydroxy silicon oil,
The addition of described structurizing treatment agent is: with 100 parts of raw-silastic continuouslies for benchmark, and the consumption of structurizing treatment agent is 0.5 ~ 4 part.
Preferably, be also added with vulcanizing agent in described low-smoke non-halogen flame-retardant silicon rubber, described vulcanizing agent is two two or five vulcanizing agents;
The addition of described vulcanizing agent is: with 100 parts of raw-silastic continuouslies for benchmark, and the consumption of vulcanizing agent is 1.5 parts.
Present invention also offers a kind of preparation method of low-smoke non-halogen flame-retardant silicon rubber, it is characterized in that, comprise the following steps:
1. raw material is taken according to above-mentioned weight part;
2. silicon rubber silicon rubber is joined in kneader, add gas-phase silica, hydroxy silicon oil several times successively, then add silicon rubber low-smoke non-halogen flame-retardant agent composition, mix homogeneous under room temperature, be warming up to 120 DEG C, vacuumize, thermal treatment 45min, takes out, and it is evenly mixing in two roller mill to add vulcanizing agent, vulcanizing press carries out sulfuration, obtains low-smoke non-halogen flame-retardant silicon rubber; Described curing temperature 170 DEG C, curing time 10min.
Beneficial effect of the present invention:
1, low-smoke non-halogen flame-retardant silicon rubber of the present invention, with the addition of silicon rubber low-smoke non-halogen flame-retardant agent composition, excellent fireproof performance, smoke suppressing effect is good, and flame retardant rating FV-0 level, oxygen index is greater than 35%, and smoke density is less than 100.
2, low-smoke non-halogen flame-retardant silicone rubber mechanical performance of the present invention is excellent, and tensile strength can reach 6.5MPa, and elongation reaches 330%.
3, the present invention relates to product (silicon rubber low-smoke non-halogen flame-retardant agent composition and low-smoke non-halogen flame-retardant silicon rubber) not containing haloid element, environmentally friendly, LSZH, environmental protection.
Embodiment
In order to understand the present invention better, illustrate content of the present invention further below in conjunction with embodiment, but content of the present invention is not only confined to the following examples, embodiment should not regard as limiting the scope of the present invention.
Embodiment 1
A kind of low-smoke non-halogen flame-retardant silicon rubber, is made up of the feed composition of following weight part:
Silicon rubber: methyl vinyl silicone rubber 100 parts;
Silicon rubber low-smoke non-halogen flame-retardant agent composition: melamine cyanurate 8 parts, aluminium hydroxide (are selected from the commercially available prod of Jinan Taixing Fine Chemicals Co., ltd, particle size range is 0.8 ~ 2 μm) 10 parts, ammonium polyphosphate (crystal II-type ammonium polyphosphate, its polymerization degree is greater than 1000) 15 parts, tetramethylolmethane 3 parts, silane coupling agent 0.2 part;
The preparation of silicon rubber low-smoke non-halogen flame-retardant agent composition: by melamine cyanurate with silane coupler modified, then by above several component mixing, obtains silicon rubber low-smoke non-halogen flame-retardant agent composition.
Strengthening agent: gas-phase silica 20 parts;
Structurizing treatment agent: hydroxy silicon oil 1 part;
Vulcanizing agent: two two or five vulcanizing agent 1.5 parts.
Above-mentioned silicon rubber preparation method: 100 parts, silicon rubber, joins in kneader, adds gas-phase silica, hydroxy silicon oil several times successively, add silicon rubber low-smoke non-halogen flame-retardant agent composition, mix under room temperature, be warming up to 120 DEG C, vacuumize, thermal treatment 45min, take out, it is evenly mixing in two roller mill to add two two or five vulcanizing agent 1.5 parts, and vulcanizing press carries out sulfuration, curing temperature 170 DEG C, curing time 10min.
Embodiment 2
A kind of low-smoke non-halogen flame-retardant silicon rubber, is made up of the feed composition of following weight part:
Silicon rubber: methyl vinyl silicone rubber 100 parts;
Silicon rubber low-smoke non-halogen flame-retardant agent composition: melamine cyanurate 10 parts, aluminium hydroxide (are selected from the commercially available prod of Jinan Taixing Fine Chemicals Co., ltd, particle size range is 0.8 ~ 2 μm) 12 parts, ammonium polyphosphate (crystal II-type ammonium polyphosphate, its polymerization degree is greater than 1000) 16 parts, tetramethylolmethane 2 parts, silane coupling agent 0.1 part;
The preparation of silicon rubber low-smoke non-halogen flame-retardant agent composition: by melamine cyanurate with silane coupler modified, then by above several component mixing, obtains silicon rubber low-smoke non-halogen flame-retardant agent composition.
Strengthening agent: gas-phase silica 30 parts;
Structurizing treatment agent: hydroxy silicon oil 2 parts;
Vulcanizing agent: two two or five vulcanizing agent 1.5 parts.
Above-mentioned silicon rubber preparation method: 100 parts, silicon rubber, joins in kneader, adds gas-phase silica, hydroxy silicon oil several times successively, add silicon rubber low-smoke non-halogen flame-retardant agent composition, mix under room temperature, be warming up to 120 DEG C, vacuumize, thermal treatment 45min, take out, it is evenly mixing in two roller mill to add two two or five vulcanizing agent 1.5 parts, and vulcanizing press carries out sulfuration, curing temperature 170 DEG C, curing time 10min.
Embodiment 3
A kind of low-smoke non-halogen flame-retardant silicon rubber, is made up of the feed composition of following weight part:
Silicon rubber: methyl vinyl silicone rubber 100 parts;
Silicon rubber low-smoke non-halogen flame-retardant agent composition: melamine cyanurate 10 parts, aluminium hydroxide (are selected from the commercially available prod of Jinan Taixing Fine Chemicals Co., ltd, particle size range is 0.8 ~ 2 μm) 12 parts, ammonium polyphosphate (crystal II-type ammonium polyphosphate, its polymerization degree is greater than 1000) 18 parts, tetramethylolmethane 3 parts, silane coupling agent 0.3 part;
The preparation of silicon rubber low-smoke non-halogen flame-retardant agent composition: by melamine cyanurate with silane coupler modified, then by above several component mixing, obtains silicon rubber low-smoke non-halogen flame-retardant agent composition.
Strengthening agent: gas-phase silica 40 parts;
Structurizing treatment agent: hydroxy silicon oil 4 parts;
Vulcanizing agent: two two or five vulcanizing agent 1.5 parts.
Above-mentioned silicon rubber preparation method: 100 parts, silicon rubber, joins in kneader, adds gas-phase silica, hydroxy silicon oil several times successively, add silicon rubber low-smoke non-halogen flame-retardant agent composition, mix homogeneous under room temperature, be warming up to 120 DEG C, vacuumize, thermal treatment 45min, take out, it is evenly mixing in two roller mill to add two two or five vulcanizing agent 1.5 parts, and vulcanizing press carries out sulfuration, curing temperature 170 DEG C, curing time 10min.
Low-smoke non-halogen flame-retardant silicon rubber in above-described embodiment is carried out flame retardant properties and measuring mechanical property, and test result is as shown in table 1 below:
The performance data of table 1 low-smoke non-halogen flame-retardant silicon rubber
Test item | Examination criteria | Embodiment 1 | Embodiment 2 | Embodiment 3 |
Fire-retardant rank | GB/T10707-2008 | FV-0 | FV-0 | FV-0 |
Oxygen index (%) | GB/T10707-2008 | 35 | 37 | 36 |
Smoke density | GB/T8323-2008 | 82.53 | 80.26 | 81.56 |
Tensile strength (MPa) | GB/T528-2009 | 6.9 | 6.6 | 6.4 |
Tensile yield (%) | GB/T528-2009 | 330 | 350 | 320 |
From the performance test results of above-described embodiment, the present invention relates to low-smoke non-halogen flame-retardant silicon rubber flame-retardant excellent performance, reach fire-retardant rank FV-0 level, flame retardant properties is good, and mechanical property is excellent, and tensile strength is greater than 6.4MPa, and tensile yield is greater than 320%.
Claims (10)
1. a silicon rubber low-smoke non-halogen flame-retardant agent composition, is characterized in that, composed of the following components: melamine cyanurate, aluminium hydroxide, ammonium polyphosphate and tetramethylolmethane,
Wherein, the weight ratio of melamine cyanurate, aluminium hydroxide, ammonium polyphosphate and tetramethylolmethane is 1 ~ 15:5 ~ 20:15 ~ 30:1 ~ 10.
2. silicon rubber low-smoke non-halogen flame-retardant agent composition according to claim 1, is characterized in that, the weight ratio of described melamine cyanurate, aluminium hydroxide, ammonium polyphosphate and tetramethylolmethane is 5 ~ 10:10 ~ 15:15 ~ 20:1 ~ 3.
3. silicon rubber low-smoke non-halogen flame-retardant agent composition according to claim 1, it is characterized in that, described melamine cyanurate is modified melamine cyanurate.
4. silicon rubber low-smoke non-halogen flame-retardant agent composition according to claim 3, is characterized in that, the properties-correcting agent of described modified melamine cyanurate is silane coupling agent, and wherein weight proportion shared by properties-correcting agent is 1% ~ 3% of melamine cyanurate.
5. silicon rubber low-smoke non-halogen flame-retardant agent composition according to claim 1, is characterized in that,
Described aluminium hydroxide particle size range is 0.8 ~ 2 μm;
Described ammonium polyphosphate is crystal II-type ammonium polyphosphate, and its polymerization degree is greater than 1000.
6. a low-smoke non-halogen flame-retardant silicon rubber, is characterized in that,
Add silicon rubber low-smoke non-halogen flame-retardant agent composition in described low-smoke non-halogen flame-retardant silicon rubber, the addition of described silicon rubber low-smoke non-halogen flame-retardant agent composition is: with 100 parts of raw-silastic continuouslies for benchmark, be no more than 35 parts;
Described silicon rubber is methyl vinyl silicon kautschuk, and its molecular weight is 50 ~ 700,000, and vinyl molar content is 0.08% ~ 0.16%.
7. low-smoke non-halogen flame-retardant silicon rubber according to claim 6, is characterized in that, is also added with strengthening agent in described low-smoke non-halogen flame-retardant silicon rubber, and described strengthening agent is gas-phase silica,
The addition of described strengthening agent is: with 100 parts of raw-silastic continuouslies for benchmark, and strengthening agent consumption is 20 ~ 40 parts.
8. low-smoke non-halogen flame-retardant silicon rubber according to claim 6, is characterized in that, is also added with structurizing treatment agent in described low-smoke non-halogen flame-retardant silicon rubber, and described structurizing treatment agent is hydroxy silicon oil,
The addition of described structurizing treatment agent is: with 100 parts of raw-silastic continuouslies for benchmark, and the consumption of structurizing treatment agent is 0.5 ~ 4 part.
9. low-smoke non-halogen flame-retardant silicon rubber according to claim 6, is characterized in that, is also added with vulcanizing agent in described low-smoke non-halogen flame-retardant silicon rubber, and described vulcanizing agent is two two or five vulcanizing agents;
The addition of described vulcanizing agent is: with 100 parts of raw-silastic continuouslies for benchmark, and the consumption of vulcanizing agent is 1.5 parts.
10. a preparation method for the arbitrary described low-smoke non-halogen flame-retardant silicon rubber of claim 6-9, is characterized in that, comprise the following steps:
1. raw material is taken according to the weight part described in claim 6-9;
2. silicon rubber silicon rubber is joined in kneader, add gas-phase silica, hydroxy silicon oil several times successively, then add silicon rubber low-smoke non-halogen flame-retardant agent composition, mix homogeneous under room temperature, be warming up to 120 DEG C, vacuumize, thermal treatment 45min, takes out, and it is evenly mixing in two roller mill to add vulcanizing agent, vulcanizing press carries out sulfuration, obtains low-smoke non-halogen flame-retardant silicon rubber; Described curing temperature 170 DEG C, curing time 10min.
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- 2014-10-30 CN CN201410598587.0A patent/CN104327511A/en active Pending
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CN105038241A (en) * | 2015-07-03 | 2015-11-11 | 东至绿洲环保化工有限公司 | Organic-silicon flame retardant prepared from recycled organic silicon rubber waste material via reprocessing, and preparation method thereof |
CN106751873A (en) * | 2015-07-06 | 2017-05-31 | 刘雷 | A kind of fire retardant containing fire-resistant synergistic composition and preparation method thereof |
CN105845291A (en) * | 2016-05-27 | 2016-08-10 | 湖南福德电气有限公司 | Temperature-resistant and insulation-protection rubber sleeve |
CN106633917A (en) * | 2016-12-28 | 2017-05-10 | 华南理工大学 | Silicon rubber material with synergetic inflaming retarding by nano inflaming retarding agent and nitrogen-phosphorus intumescent inflaming retarding agent and preparation method of silicon rubber material |
CN106633917B (en) * | 2016-12-28 | 2019-08-20 | 华南理工大学 | A kind of nano-meter flame retardants and nitrogen phosphorus system expanding fire retardant cooperative flame retardant silastic material and preparation method thereof |
CN109401328A (en) * | 2018-11-30 | 2019-03-01 | 中广核高新核材科技(苏州)有限公司 | The preparation method of novel fire resistant flame-proof silicon rubber |
CN110305365A (en) * | 2019-06-19 | 2019-10-08 | 四川汇森科技有限责任公司 | A kind of epoxy glass fiber Wet Winding Process halogen-free flame retardants and epoxy glass fiber prepreg |
CN111875968A (en) * | 2020-07-17 | 2020-11-03 | 东莞市朗晟材料科技有限公司 | Flame-retardant silicone rubber for low-pressure sealing and preparation method thereof |
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