CN115819950A - High-performance, low-smoke-density and low-heat-release-rate polycarbonate composition and preparation method thereof - Google Patents

High-performance, low-smoke-density and low-heat-release-rate polycarbonate composition and preparation method thereof Download PDF

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CN115819950A
CN115819950A CN202211642420.0A CN202211642420A CN115819950A CN 115819950 A CN115819950 A CN 115819950A CN 202211642420 A CN202211642420 A CN 202211642420A CN 115819950 A CN115819950 A CN 115819950A
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polycarbonate composition
low
methyl
silane
polycarbonate
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马海丰
陈增军
华国飞
阳赛林
赵春生
夏云兰
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Shanghai Pincheng Holding Group Co ltd
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Abstract

The invention relates to a polycarbonate composition with high performance, low smoke density and low heat release rate and a preparation method thereof. According to the invention, by introducing the unique interface treating agent, the flame retardance is improved, meanwhile, the compatibility of the filler and the resin is also improved, the interface strength of the resin and the filling raw material is increased, the using amount of the toughening agent is reduced, and the notch impact strength of the material is improved at the same time of high modulus; the smoke suppressant can achieve the effect of low smoke density while releasing low heat without adding the smoke suppressant, and achieves the smoke density and heat release of EN45545-2R1HL 3.

Description

High-performance, low-smoke-density and low-heat-release-rate polycarbonate composition and preparation method thereof
Technical Field
The invention belongs to the field of modified plastics, and particularly relates to a polycarbonate composition with high performance, low smoke density and low heat release rate and a preparation method thereof.
Background
The polycarbonate has high heat resistance and high carbon content, is widely applied to the fields with high flame retardant requirements such as rail transit, aerospace and the like, particularly, under the drive of low VOC environmental protection and recyclability, PC gradually replaces glass fiber reinforced plastics, and is widely applied to interior trim materials of rail transit and civil aviation airplanes. 4mm pure polycarbonate itself having a heat release of 280kW/m at the maximum average heat release rate 2 Particularly, in the process of extruding the plate, the residence time is up to 5min, and in the process, the resin and the fire retardant are reduced, so that the smoke density and the heat release are greatly improved. Meanwhile, under the trend of reducing weight and cost, the thickness of the product is reduced, according to simulation calculation, the thickness is reduced by 0.5mm, and the modulus of the material needs to be improved by 1000MPa to reach the original design performance. The method for improving the modulus by using the PC is to increase the filling proportion, but the cohesive energy of the material is reduced, the tensile strength and the notch impact strength of the material are reduced, and the material fails in the service life when the vibration stress amplitude is more than 16 MPa.
The CN112409770A Sichuan product is copolymerized by organosilicon/phenoxyl cyclophosphazene and compounded with an inorganic smoke suppressant, and the compound is complex in synthesis, poor in reproducibility and difficult to widely apply. In the patent, the filling amount is 5-30%, other performances except flame retardance are not represented, and more toxic and harmful nitrogen oxides can be generated in the combustion process of the phosphazene.
CN103224690A Jinfa science and technology Limited company adds inorganic sulfide into the formula to reduce the smoke density of polyolefin, polyurethane and unsaturated polyester, but only represents the emission of carbon monoxide and carbon dioxide, and the test condition is more than 50kW/m 2 Low.
CN104870563B Saudi base Global technology Co., ltd, by using a (carbonate-siloxane) copolymer, polydialkylsiliconOther copolymerization structures such as siloxane, silicone graft copolymer and the like synthesize low-smoke density and low-heat release resin, but the raw material unit price is high, so that the resin is not sold to the outside. And the copolymer has a notched impact strength of 5kJ/m for ensuring transparency 2 As described below, modification is difficult, and the transparent material such as an aircraft interior window is often used as a pure material.
CN109777073B Jinfa science and technology Co., ltd uses compound sulfonate and phosphorus-containing compound as a flame-retardant system to prepare a high-toughness low-smoke-density low-heat-release material. The high toughness method mainly comprises the steps of replacing the types of the fillers, using boehmite, realizing synergistic flame retardance and ensuring good comprehensive performance of the product. Boehmite in PC requires low acid value, particle size needs to be controlled, qualified boehmite has high unit price and low yield, and its small size is not favorable for strengthening PC material and raising modulus, so its modulus is not characterized.
Disclosure of Invention
The invention aims to solve the technical problem of providing a polycarbonate composition with high performance, low smoke density and low heat release rate and a preparation method thereof.
The invention provides a polycarbonate composition with high performance, low smoke density and low heat release rate, which comprises the following components in parts by weight:
Figure SMS_1
wherein the interface treating agent is a reaction product of an organic silicon flame retardant and a chain extender; the organic silicon flame retardant is a copolymer of branched methyl phenyl silane and methyl p-hydroxy phenyl silane; the catalyst is TiO 2
The polycarbonate is at least one of bisphenol A polycarbonate and bisphenol A branched polycarbonate.
The flame retardant is at least one of isobutyl pentaerythritol diphosphate tetraester, bis (2, 6-dimethylphenoxy) pentaerythritol tetraester and bis (2-tert-butylphenoxy) pentaerythritol tetraester.
In the copolymer of the branched methyl phenyl silane and the methyl p-hydroxyphenyl silane, the molar ratio of phenyl of the branched methyl phenyl silane is 60-80%, the weight average molecular weight is between 8000-15000, and the end group is methyl; the hydroxyl molar ratio of the methyl p-hydroxyphenyl silane is 1.5 to 3 percent, and the end group is methoxyl.
The chain extender is a long-chain ester oligomer containing an aliphatic long chain and methyl phenyl, the functionality of an epoxy functional group is 4-20, the weight average molecular weight is 6800-7250, and the epoxy equivalent is 250-300g/mol.
The epoxy equivalent of the interface treating agent is 250-500 g/mol.
The calculation of the epoxy equivalent is as follows: C1/Mw 1C 3= C2/Mw2 (4300/epoxy equivalent) N; wherein the content of the first and second substances,
the addition amount of the branched methyl phenyl silane and methyl p-hydroxyphenyl silane copolymer is-C1;
the weight average molecular weight of the branched methyl phenyl silane and methyl p-hydroxyphenyl silane copolymer is-Mw 1;
the addition amount of the chain extender is C2;
the weight average molecular weight of the branched methyl phenyl silane and methyl p-hydroxyphenyl silane copolymer is-Mw 2;
the hydroxyl content of the methyl p-hydroxy phenyl silane in the whole organic silicon flame retardant is-C3;
n- - -3 (when starting materials are specified).
The toughening agent is a compound of acrylate rubber and organic silicon rubber in a mass ratio of 1.
The TiO is 2 Can act as a Lewis acid at high temperatures and can catalyze the formation of carbon.
The filler is at least one of talcum powder and mica powder, and the mesh number is 8000-10000.
The invention provides a preparation method of a polycarbonate composition with high performance, low smoke density and low heat release rate, which comprises the following steps:
(1) Adding a chain extender into the copolymer of branched methyl phenyl silane and methyl p-hydroxyphenyl silane, and reacting at 120-150 ℃ for 2-5min to obtain an interface treating agent;
(2) According to the proportion, the interface treating agent and other components are respectively added into a double-screw extruder, and are subjected to melt extrusion and granulation to obtain the polycarbonate composition with high performance, low smoke density and low heat release rate.
The temperature of the melt extrusion is 150-260 ℃.
The length-diameter ratio of the double-screw extruder is 35-40.
The invention also provides application of the polycarbonate composition with high performance, low smoke density and low heat release rate in the wall board of the railway vehicle.
Advantageous effects
(1) The notched impact strength of the invention is high without using copolymerized Si-PC>20kJ/m 2 Above, the modulus is higher than 5500MPa at the same time;
(2) According to the invention, by introducing the unique interface treating agent, the flame retardance is improved, meanwhile, the compatibility of the filler and the resin is also improved, the interface strength of the resin and the filling raw material is increased, the using amount of the toughening agent is reduced, and the notch impact strength of the material is improved at the same time of high modulus;
(3) The invention can achieve the effect of low smoke density without adding smoke inhibitor except the filler and the flame retardant, and achieves the smoke density and the heat release of EN45545-2R1HL3 under the condition of controlling the layered filling type and the flame retardant structure.
Drawings
FIG. 1 is a graph of heat release rate measurements for example 2.
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.
The reagents, methods and equipment adopted by the invention are conventional in the technical field if no special description is given.
The following examples and comparative examples employ the following starting materials:
bisphenol a polycarbonate: the weight-average molecular weight Mw is between 40,000 and 50,000, the molecular weight distribution is between 1 and 1.5, covestro 3100.
Bisphenol a type branched polycarbonate: DSC measures Tg above 153 deg.C at 10 deg.C/min, wanhua WB2032.
Flame retardant: isobutyl pentaerythritol diphosphate pentaerythritol tetraester, diren FCX-210.
A toughening agent: a composite of acrylate rubber and silicone rubber, mitsubishi-SX 005.
TiO 2 : it is commercially available.
Mica powder: mesh 8000, commercially available.
Talc powder: mesh number 10000, commercially available.
Cross-linked methylphenylsiloxane available under the trade designation KR-2710: the more the confidence.
Chain extender: BASF ADR4468.
Interface treating agent: the reaction product of the branched methylphenylsilane and the methylparaben silane copolymer with the chain extender, typically using a polymer containing terminal hydroxyl groups that react with the polyepoxy functionality, weakens the interfacial strength between the resin and the filler; the organic silicon flame retardant is a copolymer of branched methyl phenyl silane and methyl p-hydroxy phenyl silane.
In the copolymer of the branched methyl phenyl silane and the methyl p-hydroxyphenyl silane, the molar ratio of phenyl of the branched methyl phenyl silane is 60-80%, the weight average molecular weight is between 8000-15000, and the end group is methyl; the hydroxyl molar ratio of the methyl p-hydroxyphenyl silane is 1.5 to 3 percent, and the end group is methoxyl.
The chain extender is a long-chain ester oligomer containing an aliphatic long chain and a methyl phenyl group, the functionality of an epoxy functional group is 4-20, the weight average molecular weight is 6800-7250, and the epoxy equivalent is 250-300g/mol.
The interfacial agent has an epoxy equivalent of 250g/mol or 500g/mol.
In particular, the molar ratio of phenyl groups of the methylphenylsiloxane is 74%, the weight-average molecular weight is 8500, and the molar ratio of hydroxyl groups of the methylparaben silane is 2.3%; the epoxy functions of the chain extender are all 12, the weight average molecular weight is 7000 (PS calibration), the molecular weight distribution is 1.1, and the epoxy equivalent is 270g/mol
Interface treating agent: C1/Mw 1C 3= C2/Mw2 (4300/epoxy equivalent) 3;
wherein the addition amount of the branched methyl phenyl silane and methyl p-hydroxyphenyl silane copolymer is C1;
the weight average molecular weight of the branched methyl phenyl silane and methyl p-hydroxyphenyl silane copolymer is-Mw 1;
the addition amount of the chain extender is C2;
the weight average molecular weight of the branched methyl phenyl silane and methyl p-hydroxyphenyl silane copolymer is-Mw 2;
the hydroxyl content of the methyl p-hydroxy phenyl silane in the whole organic silicon flame retardant is-C3;
specifically, the interfacial treatment agent composition ratio is C1/C2=25.2 (weight ratio).
The preparation method of the interface treating agent comprises the following steps: adding the chain extender into the copolymer of the branched methyl phenyl silane and the methyl p-hydroxy phenyl silane, and reacting for 2-5min at 150 ℃.
The composite materials of the examples and comparative examples were prepared by the following procedure:
and (3) adding the interface treating agent and other components into a double-screw extruder respectively according to the proportion, and carrying out melt extrusion and granulation to obtain the composite material. The length-diameter ratio of the twin-screw extruder is 40. The water content of all raw materials is controlled below 0.05 percent during production.
The temperature of the melt extrusion is
First stage Second section Third stage Fourth stage Fifth stage Sixth stage Seventh stage Eighth paragraph Ninth paragraph The tenth section
150℃ 255℃ 255℃ 255℃ 250℃ 250℃ 260℃ 250℃ 250℃ 250℃
Main screw rotation speed Rotational speed of side feeder Vacuum pressure
400±50rpm 40±10Hz >0.07MPa
The examples and comparative examples were subjected to the following test methods or test standards:
item Standard of merit Condition
Smoke density Ds4 ISO 5659 50kW/m 2 Flameless lighting device
Smoke density VOF (4) ISO 5659 50kW/m 2 Flameless
Heat release MARHE ISO 5660 50kW/m 2
Flexural modulus ISO 178 2mm/min
Tensile strength ISO 527-1,-2 50mm/min
Notched impact strength ISO 179 Machining A-shaped notch at 23 ℃/min
Notched impact strength ISO 179 Machining A-shaped notch at-25 DEG C
Figure SMS_2
Conclusion 1
a. The interface treating agent can replace a toughening agent, so that the aim of high modulus is fulfilled while the notch impact of the material is improved, but the modulus is slightly reduced due to the addition of the interface treating agent, and the effect of improving the modulus is reduced due to better compatibility.
b. The modulus of the material using the branched PC is improved in a reduced range, because the fluidity of the branched PC is reduced, the orientation of the filler is influenced, but the entanglement among molecules is more, the dispersion force is larger, and therefore the notch impact strength is greatly improved
C. The talc powder has a greater modulus increase and a lesser impact on notched impactor strength than mica powder, which may be related to the effect of the degree of reaction of the filler surface functional groups with the interfacial treatment agent.
Figure SMS_3
Conclusion 2
a. A reduction in the content of flame retardant leads to an increase in the notched impact strength of the material, but a corresponding reduction in the modulus, since this flame retardant has a partial plasticizing effect and leads to a material;
b. the epoxy equivalent is increased, the modulus of the material is reduced, because the epoxy equivalent is increased, the chain extension and compatibilization effects are stronger, the notch impact strength is increased, and the modulus is reduced;
c. the proper addition amount of the interface treating agent is 2-5 parts, and the interface strength cannot be increased but the smoke density of the product can be increased by continuously adding the interface treating agent, because the crosslinking reaction can be increased during heating to delay degradation, but the interface treating agent can release more smoke.

Claims (10)

1. A high performance, low smoke density, low heat release rate polycarbonate composition characterized by: the paint comprises the following components in parts by weight:
Figure FDA0004008150390000011
wherein the interface treating agent is a reaction product of an organic silicon flame retardant and a chain extender; the organic silicon flame retardant is a copolymer of branched methyl phenyl silane and methyl p-hydroxy phenyl silane; the catalyst is TiO 2
2. The polycarbonate composition of claim 1, wherein: the polycarbonate is at least one of bisphenol A polycarbonate and bisphenol A branched polycarbonate.
3. The polycarbonate composition of claim 1, wherein: the fire retardant is a screen throwing atomic clock in isobutyl dipentaerythritol phosphate tetraester, bis (2, 6-dimethylphenoxy) pentaerythritol tetraester and bis (2-tert-butylphenoxy) pentaerythritol tetraester.
4. The polycarbonate composition of claim 1, wherein: in the copolymer of the branched methyl phenyl silane and the methyl p-hydroxyphenyl silane, the molar ratio of phenyl of the branched methyl phenyl silane is 60-80%, the weight average molecular weight is between 8000-15000, and the end group is methyl; the molar ratio of hydroxyl of the methyl p-hydroxyphenyl silane is 1.5 to 3 percent, and the end group is methoxyl.
5. The polycarbonate composition of claim 1, wherein: the chain extender is a long-chain ester oligomer containing an aliphatic long chain and a methyl phenyl group, the functionality of an epoxy functional group is 4-20, the weight average molecular weight is 6800-7250, and the epoxy equivalent is 250-300g/mol.
6. The polycarbonate composition of claim 1, wherein: the epoxy equivalent of the interface treating agent is 250-500 g/mol.
7. The polycarbonate composition of claim 1, wherein: the toughening agent is a compound of acrylate rubber and organic silicon rubber.
8. The polycarbonate composition of claim 1, wherein: the filler is at least one of talcum powder and mica powder, and the mesh number is 8000-10000.
9. A preparation method of a polycarbonate composition with high performance, low smoke density and low heat release rate comprises the following steps:
(1) Adding a chain extender into the copolymer of branched methyl phenyl silane and methyl p-hydroxyphenyl silane, and reacting at 120-150 ℃ for 2-5min to obtain an interface treating agent;
(2) According to the proportion of claim 1, the interface treating agent and other components are respectively added into a double-screw extruder, and then melt extrusion and granulation are carried out, thus obtaining the polycarbonate composition with high performance, low smoke density and low heat release rate.
10. Use of a high performance, low smoke density, low heat release rate polycarbonate composition according to claim 1 in a rail vehicle wallboard.
CN202211642420.0A 2022-12-20 2022-12-20 High-performance, low-smoke-density and low-heat-release-rate polycarbonate composition and preparation method thereof Pending CN115819950A (en)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104497536A (en) * 2014-12-26 2015-04-08 深圳华力兴新材料股份有限公司 Flame-retardant polycarbonate composition and preparation method thereof
CN109293853A (en) * 2018-09-11 2019-02-01 铨盛聚碳科技股份有限公司 A kind of organic silicon fibre retardant and preparation method thereof containing epoxy group
CN110157174A (en) * 2019-05-30 2019-08-23 深圳华力兴新材料股份有限公司 A kind of the fire-retardant polycarbonate composite material and preparation method and application of glass fiber reinforcement
CN112266619A (en) * 2020-11-02 2021-01-26 广东圆融新材料有限公司 Polycarbonate composition resistant to wet heat aging and preparation method thereof
CN114316561A (en) * 2021-12-29 2022-04-12 上海品诚控股集团有限公司 High-gloss low-filling halogen-free hybrid flame-retardant PC material and preparation and application thereof
CN115322552A (en) * 2022-08-29 2022-11-11 南京聚隆科技股份有限公司 Low-smoke low-heat-release polycarbonate material for rail transit interior decoration

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104497536A (en) * 2014-12-26 2015-04-08 深圳华力兴新材料股份有限公司 Flame-retardant polycarbonate composition and preparation method thereof
CN109293853A (en) * 2018-09-11 2019-02-01 铨盛聚碳科技股份有限公司 A kind of organic silicon fibre retardant and preparation method thereof containing epoxy group
CN110157174A (en) * 2019-05-30 2019-08-23 深圳华力兴新材料股份有限公司 A kind of the fire-retardant polycarbonate composite material and preparation method and application of glass fiber reinforcement
CN112266619A (en) * 2020-11-02 2021-01-26 广东圆融新材料有限公司 Polycarbonate composition resistant to wet heat aging and preparation method thereof
CN114316561A (en) * 2021-12-29 2022-04-12 上海品诚控股集团有限公司 High-gloss low-filling halogen-free hybrid flame-retardant PC material and preparation and application thereof
CN115322552A (en) * 2022-08-29 2022-11-11 南京聚隆科技股份有限公司 Low-smoke low-heat-release polycarbonate material for rail transit interior decoration

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