CN102585502A - Preparation method of high-temperature polymer matrix PTC (positive temperature coefficient) material with delay NTC (negative temperature coefficient) effect - Google Patents
Preparation method of high-temperature polymer matrix PTC (positive temperature coefficient) material with delay NTC (negative temperature coefficient) effect Download PDFInfo
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Abstract
The invention relates to a preparation method of a high-temperature polymer matrix PTC (positive temperature coefficient) material with a delay NTC (negative temperature coefficient) effect. The materials comprise the following components by weight percent: 3-15% of conductive carbon black (CB), 42.5-67.9% of polymer matrix polyphenylene sulfide (PPS) and 25.5-48.5% of polytetrafluoroethylene (PTFE), wherein the mass ratio of PPS to PTFE is (5/5)-(7/3). The method comprises the following steps of: carrying out coupling agent modification treatment on the CB, dispersing the CB with the PPS powder and the PFE powder in absolute ethyl alcohol, ball-milling uniformly, then volatilizing a solvent, and sintering under hot pressing at a certain temperature so as to obtain a CB/PPS/PTFE composite material. The high-temperature polymer matrix PTC material with the delay NTC effect, disclosed by the invention, has the characteristics of eliminating the NTC effect without radiation crosslinking by crosslinking devices, reducing the manufacturing cost, simplifying the production process, the room-temperature resistivity of the composite material can be adjusted by adjusting the CB content and the weight ratio of PPS to PTFE.
Description
Technical field
The present invention relates to the polymer matrix PTC matrix material in a kind of hyundai electronics and electric works field, relate to a kind of preparation method with the high temperature polymer matrix PTC material that postpones the NTC effect.
Technical background
The manufacturing of ptc polymer is a body material with Vilaterm (PE), ethylene-vinyl acetate copolymer (EVA), pvdf single component crystallizations such as (PVDF) or semi-crystalline polymer mainly at present; The fusing point of these polymeric matrix material causes the use temperature of final polymer matrix PTC material not high generally all less than 150 ℃.Simultaneously, this type ptc material could use after in the course of processing, often needing radiation crosslinking to eliminate the NTC effect, otherwise material is when in use causing the temperature rising near the fusing point of polymeric matrix because of energising, and polymkeric substance can deform even burn.But the radiation crosslinking treating processes of ptc material need be used expensive cross-linking apparatus, and this can improve the production cost of material.Along with making rapid progress of modern science and technology, the ptc polymer Application Areas is constantly expanded, and the needs exploitation is easy to process, cheap for manufacturing cost, use temperature is higher (the PTC transition temperature is higher than 200 ℃) and the polymer matrix PTC material of excellent combination property.Present PE, EVA, PP and PVDF single-component polymer matrix PTC material all can't satisfy the requirement that 200 ℃ of high temperature use.Through using dystectic semicrystalline polymeric material is the basic skills that improves the polymer matrix PTC material use temperature as matrix; Adopt two or more polymer blendings to form polynary compound system; Matrix material had be different from the novel special performance of single polymers matrix; Realize the mutual supplement with each other's advantages of each component, even represent the function that makes new advances.Therefore, multipolymer matrix blended compound material more and more receives people's attention in the research and development of polymer matrix PTC material.
Summary of the invention
The purpose of this invention is to provide a kind of preparation method with high temperature polymer matrix PTC material of remarkable delay NTC effect.
A kind of preparation method with the high temperature polymer matrix PTC material that postpones the NTC effect of the present invention is characterized in that:
1) raw material: described high temperature polymer matrix PTC material with delay NTC effect has following material to form: conductive filler material CB, polymeric matrix material PPS and PTFE; Described CB conductive filler material accounts for 3.0% ~ 15.0% of matrix material total mass; Said polymeric matrix PPS content 42.5% ~ 67.9%, PTFE content 25.5% ~ 48.5%, wherein PPS and PTFE mass ratio are 5/5 ~ 7/3; Described CB conductive filler material median size is 50nm, after silane coupling agent is handled, uses, and wherein the mass ratio of silane coupling agent and CB is 100:1; Described polymeric matrix PPS fusing point is 285 ℃, and median size is 20 μ m; Described polymeric matrix PTFE fusing point is 327 ℃, and melt viscosity is 10
10Pas, median size is 25 μ m;
2) surface treatment of CB conductive filler material: make it in absolute ethyl alcohol, form suspension-s through ultra-sonic dispersion and stirring in the CB powder under the room temperature, add then and continue behind the coupling agent to stir 10 ~ 30 minutes; Add deionized water subsequently, at 40 ~ 60 ℃ of following ultra-sonic dispersion and stirred 15 ~ 60 minutes; The spinning powder, use absolute ethanol washing 1 ~ 3 time then after, 60 ~ 120 ℃ of following vacuum-dryings 2 ~ 5 hours, use after naturally cooling to room temperature; Wherein coupling agent is a γ-An Bingjisanyiyangjiguiwan;
3) compound: take by weighing the silane coupler modified CB powder that obtains in PPS and PTFE powder and the step (2), the quality percentage composition that makes the CB conductive filler material is 3.0 ~ 15.0%; Polymeric matrix PPS quality percentage composition is 42.5% ~ 67.9%; PTFE quality percentage composition is 25.5% ~ 48.5%; Wherein PTFE and PPS mass ratio are 5/5 ~ 7/3; Then CB powder, PPS powder and PTFE powder are disperseed in ethanol, ball mill mixing is back evaporating solvent in baking oven evenly, places dry 1 h under 120 ℃ of conditions of vacuum drying oven then, obtains mixed powder;
4) moulding: as in the sintered-carbide die, in hot pressing 15 minutes under 100 MPa pressure under 330 ~ 380 ℃, obtaining diameter behind the cool to room temperature is 20 mm with mixed powder, and thickness is the disk shape sample of 1 ~ 3 mm.
The present invention has following beneficial effect: this polymer PTC matrix material has the transition temperature up to 250 ℃, can use as the high-temp PTC material; The NTC effect of matrix material is deferred to about 335 ℃ from 295 ℃, has postponed about 40 ℃, has avoided expensive radiation crosslinking technology, has simplified the ME of ptc material, has reduced production cost; Composite material by adopting resistant to elevated temperatures polymeric matrix PPS and PTFE, itself does not fire, and has guaranteed the security that material uses, and does not need the poisonous halogen containing flame-retardant of extra interpolation; Matrix material can pass through the electroconductibility of content and PPS and the PTFE weight ratio change matrix material of adjusting CB, therefore can control the room-temperature conductivity of matrix material comparatively accurately.
Description of drawings
Fig. 1 prepares the process flow sheet of polymer PTC matrix material for the present invention;
Fig. 2 is 8 wt% for CB conductive filler material content, and polymeric matrix PPS and PTFE mass ratio are respectively the DSC curve of 7/3,6/4,5/5 o'clock CB/PPS/PTFE matrix material;
Fig. 3 is 8wt% for CB conductive filler material content, PPS/PTFE=5/5 (w/w), CB/PPS/PTFE matrix material
Resistance-temperature curve;
Fig. 4 is 8wt% for CB conductive filler material content, PPS/PTFE=7/3 (w/w), CB/PPS/PTFE matrix material
Resistance-temperature curve;
Fig. 5 is 12wt% for CB conductive filler material content, PPS/PTFE=5/5 (w/w), the resistance-temperature curve of CB/PPS/PTFE composite wood;
Fig. 6 is 9wt% for CB conductive filler material content, PPS/PTFE=5/5 (w/w), CB/PPS/PTFE matrix material
Resistance-temperature curve;
Fig. 7 is 9wt% for CB conductive filler material content, PPS/PTFE=6/4 (w/w), CB/PPS/PTFE matrix material
Resistance-temperature curve;
Fig. 8 is 9wt% for CB conductive filler material content, PPS/PTFE=7/3 (w/w), CB/PPS/PTFE matrix material
Resistance-temperature curve.
Embodiment
Below through combining specific embodiment that the present invention is done further detailed description.Embodiment only is to a kind of explanation of the present invention, and is not construed as limiting the invention.Embodiment is the practical application example, is easy to grasp and checking for those skilled in the art.If on basis of the present invention, make certain change, its essence does not exceed scope of the present invention so.
Embodiment 1
(1) makes it in absolute ethyl alcohol, form suspension-s through ultra-sonic dispersion and stirring in 100 g CB conductive filler material powder under the room temperature, add 1 g coupling agent (γ-An Bingjisanyiyangjiguiwan) back then and continue to stir 10 ~ 30 minutes; Add deionized water subsequently, at 40 ~ 60 ℃ of following ultra-sonic dispersion and stirred 15 ~ 60 minutes; The spinning powder, use absolute ethanol washing 1 ~ 3 time then after, 60 ~ 120 ℃ of following vacuum-dryings 2 ~ 5 hours, use after naturally cooling to room temperature;
(2) take by weighing silane coupler modified CB powder 0.5438 g that obtains in 3.1269 g PPS and 3.1269 g PTFE powder and the step (1); The quality percentage composition that makes the CB conductive filler material is 8%, and polymeric matrix PPS quality percentage composition is 46%, and PTFE quality percentage composition is 46%, and wherein PPS and PTFE mass ratio are 5/5; CB powder, PPS powder and PTFE powder are disperseed in ethanol, and ball mill mixing is back evaporating solvent in baking oven evenly, places dry 1 h under 120 ℃ of conditions of vacuum drying oven then, obtains mixed powder;
(3) moulding: as in the sintered-carbide die, in hot pressing 15 minutes under 100 MPa pressure under 360 ℃, obtaining diameter behind the cool to room temperature is 20 mm with mixed powder, and thickness is the disk shape sample of 1 ~ 3 mm;
(4) the preparation flow figure of matrix material sees accompanying drawing 1 among the embodiment 1-6; With the sample 5-10 mg sample that blade cuts step (3) obtains, in nitrogen, temperature rise rate is the DSC curve of measure sample under the 20 ℃/min condition, and its result sees curve c in the accompanying drawing 2; Starch in 100 ℃ at the sample two ends coated with conductive silver that step (3) obtains and to handle 1h, 24h stablize in the cooling back naturally, silver is starched and chip material reaches ohmic contact, specimen resistance-temperature characteristics then, and its result sees accompanying drawing 3: room temperature resistivity is 151 Ω cm; PTC changes since 250 ℃, and to 295 ℃ of end, PTC intensity is 2.5; The NTC effect takes place after being deferred to 335 ℃ from 295 ℃, has postponed 40 ℃.
(1) process of surface treatment of CB conductive filler material powder is with instance 1;
(2) take by weighing silane coupler modified CB powder 0.5502 g that obtains in 4.4291 g PPS and 1.8982 g PTFE powder and the step (1); The quality percentage composition that makes the CB conductive filler material is 8%, and polymeric matrix PPS quality percentage composition is 64.4%, and PTFE quality percentage composition is 27.6%, and wherein PPS and PTFE mass ratio are 7/3; CB powder, PPS powder and PTFE powder are disperseed in ethanol, and ball mill mixing is back evaporating solvent in baking oven evenly, places dry 1 h under 120 ℃ of conditions of vacuum drying oven then, obtains mixed powder;
(3) moulding: as in the sintered-carbide die, in hot pressing 15 minutes under 50 MPa pressure under 380 ℃, obtaining diameter behind the cool to room temperature is 20 mm with mixed powder, and thickness is the disk shape sample of 1 ~ 3 mm;
(4) the DSC curve test condition of sample is with embodiment 1, and the result sees curve a in the accompanying drawing 2; Sample resistance-temperature characteristics testing method is with embodiment 1, and its result sees accompanying drawing 4: room temperature resistivity is 319 Ω cm; PTC changes since about 250 ℃, and to 290 ℃ of end, PTC intensity is 4.7; The NTC effect takes place after being deferred to 335 ℃ from 290 ℃, has postponed 45 ℃.
(1) process of surface treatment of CB conductive filler material powder is with instance 1;
(2) take by weighing silane coupler modified CB powder 0.6732 g that obtains in 2.4684 g PPS and 2.4684 g PTFE powder and the step (1); The quality percentage composition that makes the CB conductive filler material is 12%, and polymeric matrix PPS quality percentage composition is 44%, and PTFE quality percentage composition is 44%, and wherein PPS and PTFE mass ratio are 5/5; CB powder, PPS powder and PTFE powder are disperseed in ethanol, and ball mill mixing is back evaporating solvent in baking oven evenly, places dry 1 h under 120 ℃ of conditions of vacuum drying oven then, obtains mixed powder;
(3) moulding: as in the sintered-carbide die, in hot pressing 15 minutes under 100 MPa pressure under 340 ℃, obtaining diameter behind the cool to room temperature is 20 mm with mixed powder, and thickness is the disk shape sample of 1 ~ 3 mm;
(4) sample resistance-temperature characteristics testing method is with embodiment 1, and its result sees accompanying drawing 5: room temperature resistivity is 30 Ω cm; PTC changes since about 250 ℃, and to 295 ℃ of end, PTC intensity is 0.8; The NTC effect takes place after being deferred to 335 ℃ from 295 ℃, has postponed 40 ℃.
(1) process of surface treatment of CB conductive filler material powder is with instance 1;
(2) take by weighing silane coupler modified CB powder 0.5838 g that obtains in 2.9514 g PPS and 2.9514 g PTFE powder and the step (1); The quality percentage composition that makes the CB conductive filler material is 9%, and polymeric matrix PPS quality percentage composition is 45.5%, and PTFE quality percentage composition is 45.5%, and wherein PPS and PTFE mass ratio are 5/5; CB powder, PPS powder and PTFE powder are disperseed in ethanol, and ball mill mixing is back evaporating solvent in baking oven evenly, places dry 1 h under 120 ℃ of conditions of vacuum drying oven then, obtains mixed powder;
(3) moulding: as in the sintered-carbide die, in hot pressing 15 minutes under 80 MPa pressure under 360 ℃, obtaining diameter behind the cool to room temperature is 20 mm with mixed powder, and thickness is the disk shape sample of 1 ~ 3 mm;
(4) sample resistance-temperature characteristics testing method is with embodiment 1, and its result sees accompanying drawing 6: room temperature resistivity is 102 Ω cm; PTC changes since about 250 ℃, and to 295 ℃ of end, PTC intensity is 2.4; The NTC effect takes place after being deferred to 335 ℃ from 295 ℃, has postponed 40 ℃.
(1) process of surface treatment of CB conductive filler material powder is with instance 1;
(2) take by weighing silane coupler modified CB powder 0.6124 g that obtains in 3.7152 g PPS and 2.4768 g PTFE powder and the step (1); The quality percentage composition that makes the CB conductive filler material is 9%, and polymeric matrix PPS quality percentage composition is 54.6%, and PTFE quality percentage composition is 36.4%, and wherein PPS and PTFE mass ratio are 6/4; CB powder, PPS powder and PTFE powder are disperseed in ethanol, and ball mill mixing is back evaporating solvent in baking oven evenly, places dry 1 h under 120 ℃ of conditions of vacuum drying oven then, obtains mixed powder;
(3) moulding: as in the sintered-carbide die, in hot pressing 15 minutes under 50 MPa pressure under 340 ℃, obtaining diameter behind the cool to room temperature is 20 mm with mixed powder, and thickness is the disk shape sample of 1 ~ 3 mm;
(4) the DSC curve test condition of sample is with embodiment 1, and the result sees curve b in the accompanying drawing 2; Sample resistance-temperature characteristics testing method is with embodiment 1, and its result sees accompanying drawing 6: room temperature resistivity is 402 Ω cm; PTC changes since about 250 ℃, and to 285 ℃ of end, PTC intensity is 3.7; The NTC effect takes place after being deferred to 330 ℃ from 285 ℃, has postponed 40 ℃.
(1) process of surface treatment of CB conductive filler material powder is with instance 1;
(2) take by weighing silane coupler modified CB powder 0.5428 g that obtains in 3.8418 g PPS and 1.6465 g PTFE powder and the step (1); The quality percentage composition that makes the CB conductive filler material is 9%, and polymeric matrix PPS quality percentage composition is 63.7%, and PTFE quality percentage composition is 27.3%, and wherein PPS and PTFE mass ratio are 7/3; CB powder, PPS powder and PTFE powder are disperseed in ethanol, and ball mill mixing is back evaporating solvent in baking oven evenly, places dry 1 h under 120 ℃ of conditions of vacuum drying oven then, obtains mixed powder;
(3) moulding: as in the sintered-carbide die, in hot pressing 15 minutes under 50 MPa pressure under 340 ℃, obtaining diameter behind the cool to room temperature is 20 mm with mixed powder, and thickness is the disk shape sample of 1 ~ 3 mm;
(4) sample resistance-temperature characteristics testing method is with embodiment 1, and its result sees accompanying drawing 6: room temperature resistivity is 896 Ω cm; PTC changes since about 250 ℃, and to 300 ℃ of end, PTC intensity is 4.8; The NTC effect takes place after being deferred to 335 ℃ from 300 ℃, has postponed 35 ℃.
Claims (1)
1. preparation method with the high temperature polymer matrix PTC material that postpones the NTC effect is characterized in that method is:
1) raw material: described high temperature polymer matrix PTC material with delay NTC effect has following material to form: conductive filler material CB, polymeric matrix material PPS and PTFE; Described CB conductive filler material accounts for 3.0% ~ 15.0% of matrix material total mass; Said polymeric matrix PPS content 42.5% ~ 67.9%, PTFE content 25.5% ~ 48.5%, wherein PPS and PTFE mass ratio are 5/5 ~ 7/3; Described CB conductive filler material median size is 50nm, after silane coupling agent is handled, uses, and wherein the mass ratio of silane coupling agent and CB is 100:1; Described polymeric matrix PPS fusing point is 285 ℃, and median size is 20 μ m; Described polymeric matrix PTFE fusing point is 327 ℃, and melt viscosity is 10
10Pas, median size is 25 μ m;
2) surface treatment of CB conductive filler material: make it in absolute ethyl alcohol, form suspension-s through ultra-sonic dispersion and stirring in the CB powder under the room temperature, add then and continue behind the coupling agent to stir 10 ~ 30 minutes; Add deionized water subsequently, at 40 ~ 60 ℃ of following ultra-sonic dispersion and stirred 15 ~ 60 minutes; The spinning powder, use absolute ethanol washing 1 ~ 3 time then after, 60 ~ 120 ℃ of following vacuum-dryings 2 ~ 5 hours, use after naturally cooling to room temperature; Wherein coupling agent is a γ-An Bingjisanyiyangjiguiwan;
3) compound: take by weighing the silane coupler modified CB powder that obtains in PPS and PTFE powder and the step (2), the quality percentage composition that makes the CB conductive filler material is 3.0 ~ 15.0%; Polymeric matrix PPS quality percentage composition is 42.5% ~ 67.9%; PTFE quality percentage composition is 25.5% ~ 48.5%; Wherein PTFE and PPS mass ratio are 5/5 ~ 7/3; Then CB powder, PPS powder and PTFE powder are disperseed in ethanol, ball mill mixing is back evaporating solvent in baking oven evenly, places dry 1 h under 120 ℃ of conditions of vacuum drying oven then, obtains mixed powder;
4) moulding: as in the sintered-carbide die, in hot pressing 15 minutes under 100 MPa pressure under 330 ~ 380 ℃, obtaining diameter behind the cool to room temperature is 20 mm with mixed powder, and thickness is the disk shape sample of 1 ~ 3 mm.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104129148A (en) * | 2014-08-01 | 2014-11-05 | 广东生益科技股份有限公司 | Preparation method of PTFE (polytetrafluoroethylene)composite medium substrate for microwave circuit |
| CN107663367A (en) * | 2016-07-28 | 2018-02-06 | 广科工业股份有限公司 | Low dielectric constant materials and precursors thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1629215A (en) * | 2004-10-28 | 2005-06-22 | 复旦大学 | Temperature sensing material with negative temperature coefficient effect and method for preparing same |
| US20110297891A1 (en) * | 2009-10-30 | 2011-12-08 | Sabic Innovative Plastics Ip B.V. | Positive temperature coefficient materials with reduced negative temperature coefficient effect |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1629215A (en) * | 2004-10-28 | 2005-06-22 | 复旦大学 | Temperature sensing material with negative temperature coefficient effect and method for preparing same |
| US20110297891A1 (en) * | 2009-10-30 | 2011-12-08 | Sabic Innovative Plastics Ip B.V. | Positive temperature coefficient materials with reduced negative temperature coefficient effect |
Non-Patent Citations (1)
| Title |
|---|
| 谢鸿峰等: "辐射效应对LDPE/CB复合电性能的影响", 《辐射研究与辐射工艺学报》, vol. 19, no. 4, 30 November 2001 (2001-11-30), pages 294 - 297 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104129148A (en) * | 2014-08-01 | 2014-11-05 | 广东生益科技股份有限公司 | Preparation method of PTFE (polytetrafluoroethylene)composite medium substrate for microwave circuit |
| CN107663367A (en) * | 2016-07-28 | 2018-02-06 | 广科工业股份有限公司 | Low dielectric constant materials and precursors thereof |
| CN107663367B (en) * | 2016-07-28 | 2020-06-16 | 广科工业股份有限公司 | Low dielectric constant materials and precursors thereof |
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