Summary of the invention
The purpose of the present invention is to provide a kind of PTC circuit protection elements.
PTC circuit protection element of the present invention includes: a positive temperature coefficient polymer material and two electrodes,
The electrode contacts the positive temperature coefficient polymer material.
The positive temperature coefficient polymer material includes a polymeric matrix and a conductive filler, the conductive fill
Object is scattered in the polymeric matrix, which includes several first titanium carbide granules and several second titanium carbides
Grain.The polymeric matrix is made of a polymers compositions (composition), which includes a polyolefin
The selectively graft type polyolefin of substrate and one.First titanium carbide granule is micro- less than 2.5 μm of average Fei Shi with one
Partial size and first particle diameter distribution are sieved, which defines a D10 partial size less than 1.6 μm, and a D50 partial size is less than
4.5 μm and a D90 partial size are less than 22.0 μm.Second titanium carbide granule has an average Fei Shi Microtraps grain less than 3.2 μm
Diameter and second particle diameter distribution, second particle diameter distribution define a D10 partial size less than 2.5 μm, and a D50 partial size is less than 6.5 μ
M and a D90 partial size are less than 34.0 μm.There is first titanium carbide granule one to be greater than the first titanium carbide granule gross weight
The residual oxygen content of 0.3wt%.
Preferably, aforementioned PTC circuit protection element, wherein the average Fei Shi of first titanium carbide granule is micro-
Partial size is sieved less than 1.4 μm.
Preferably, aforementioned PTC circuit protection element, wherein total based on the positive temperature coefficient polymer material
Weight, the content range of the polymeric matrix are 8wt% to 20wt%, the content range of the conductive filler be 80wt% extremely
92wt%.
Preferably, aforementioned PTC circuit protection element, wherein first titanium carbide granule and second titanium carbide
The range of the weight ratio of particle is 1:9 to 9:1.
Preferably, aforementioned PTC circuit protection element, wherein the D90 partial size of first particle diameter distribution is less than
12.0μm。
Preferably, aforementioned PTC circuit protection element, wherein second titanium carbide granule have one be less than this
The residual oxygen content of two titanium carbide granule gross weight 0.3wt%.
Preferably, aforementioned PTC circuit protection element, wherein the polyolefin-based bottom is high density polyethylene (HDPE), should
Graft type polyolefin is carboxylic acid anhydrides graft type high density polyethylene (HDPE).
The beneficial effects of the present invention are: first titanium carbide granule and second titanium carbide granule are utilized, in turn
Improve the electrical stability of PTC circuit protection element of the present invention.
Specific embodiment
The following describes the present invention in detail with reference to the accompanying drawings and embodiments.
Refering to fig. 1, an embodiment of PTC circuit protection element of the present invention includes a positive temperature coefficient polymerization
Object material 2 and two contact the electrode 3 of the positive temperature coefficient polymer material 2.
The positive temperature coefficient polymer material 2 includes a polymeric matrix 21 and a conductive filler 22.The conduction
Filler 22 is scattered in the polymeric matrix 21.The conductive filler 22 includes several first titanium carbide granules and several
Second titanium carbide granule.
The polymeric matrix 21 is made of a polymers compositions, which contains a polyolefin-based bottom,
An and selectively graft type polyolefin.
It is noted that the polyolefin-based bottom can be non-grafted type polyethylene in this embodiment of the invention.
In this embodiment, which is high density polyethylene (HDPE), which is carboxylic acid anhydrides graft type
High density polyethylene (HDPE).
Based on 2 gross weight of positive temperature coefficient polymer material, the content range of the polymeric matrix 21 be 8wt% extremely
20wt%, the content range of the conductive filler 22 are 80wt% to 92wt%.
The range of the weight ratio of first titanium carbide granule and second titanium carbide granule is 1:9 to 9:1.
First titanium carbide granule has an average Fei Shi Microtraps partial size and first partial size less than 2.5 μm
Distribution, first particle diameter distribution define a D10 partial size less than 1.6 μm, and a D50 partial size is less than less than 4.5 μm and a D90 partial size
22.0μm。
In some concrete examples of the embodiment, the average Fei Shi Microtraps partial size of first titanium carbide granule is less than
1.4μm.The D90 partial size of first particle diameter distribution is less than 12.0 μm.
Second titanium carbide granule has an average Fei Shi Microtraps partial size and second partial size less than 3.2 μm
Distribution, second particle diameter distribution define a D10 partial size less than 2.5 μm, and a D50 partial size is less than less than 6.5 μm and a D90 partial size
34.0μm。
There is first titanium carbide granule residual oxygen of a 0.3wt% for being greater than the first titanium carbide granule gross weight to contain
Amount.
The residual oxygen content of second titanium carbide granule is less than the residual oxygen content of first titanium carbide granule.In the embodiment
In, which can have the residual oxygen content for being less than the second titanium carbide granule gross weight 0.3wt%.
It is below the concrete example and comparative example of the embodiment of the present invention, and is not limited the scope of the invention with this.
<concrete example 1 (E1)>
10.5 grams of high density polyethylene (HDPE) (HDPE) is used as polyolefin-based bottom, 10.5 grams of maleic anhydride (maleic
Anhydride) graft type HDPE, 64.5 grams of first the first titanium carbide granule of type (hereinafter referred to as A1 particle) and 64.5 grams
First the second titanium carbide granule of type (hereinafter referred to as B1 particle) is kneaded in a Brabender kneading machine.The average of A1 particle is taken
Family name's Microtraps partial size is 1.35 μm, and residual oxygen content is 0.9% (being shown in table 1).Also there is A1 particle a particle diameter distribution to define a D10
1.405 μm of partial size, 3.8 μm of a D50 partial size and 11.79 μm of a D90 partial size (being shown in table 1).A1 particle passes through at about 1850 DEG C
It is carbonized made by titanium dioxide and carbon particle.The average Fei Shi Microtraps partial size of B1 particle is 2.65 μm, and residual oxygen content is 0.2%
(being shown in table 1).Also there is B1 particle a particle diameter distribution to define 1.663 μm of a D10 partial size, 4.585 μm of a D50 partial size and one
22.371 μm of D90 partial size (being shown in table 1).B1 particle is by made by the about 2200 DEG C of carbonization titanium dioxide and carbon particle.It should
Melting temperature is 200 DEG C, mixing speed 50rpm, and pressurization weight is 5kg, and mixing time is 10 minutes.Compounding mixture warp
Hot pressing and the thin slice for being pressed into the positive temperature coefficient polymer material 2, thickness are 0.28mm.The hot pressing temperature is 200 DEG C, heat
The pressure time is 4 minutes and the hot pressing pressure is 80kg/cm2.Two copper foils are contacted to two opposite sides of the thin slice, and in heat
Pressing temperature is 200 DEG C, and hot pressing time is 4 minutes and the hot pressing pressure is 80kg/cm2In the environment of hot pressing to form a positive temperature
Spend coefficient laminar structure.The positive temperature coefficient laminar structure is cut into several test samples having a size of 4.5mm × 3.2mm.
The electrical characteristics result of the test sample of concrete example 1 is shown in table 3.
In table 3, R indicates resistance (ohm), and V-R indicates volume resistivity (ohm × cm).The positive temperature in concrete example 1
Spending coefficient polymer material has a polymeric matrix (weight ratio at polyolefin-based bottom and graft type polyolefin containing 14wt%
It is 1:1), the component of the second titanium carbide granule of the first titanium carbide granule and 43wt% of 43wt%.
<concrete example 2 to 6 (E1 to E6)>
The production process and condition of the production process of concrete example 2 to 6 concrete example 1 similar with condition, are different in poly-
Alkylene bottom, graft type polyolefin and the first and second titanium carbide granule content.The electricity of the test sample of the concrete example 2 to 6 is special
Property result is shown in table 3.
<concrete example 7 and 8 (E7 and E8)>
The production process and condition of the production process of concrete example 7 and 8 concrete example 1 similar with condition, are different in tool
Body example 7 and 8 uses 64.5 grams of the second titanium carbide granule of second type (hereinafter referred to as B2 particle).B2 particle is flat with 3.1 μm
Equal Fei Shi Microtraps partial size and 0.2% residual oxygen content.B2 particle also has a particle diameter distribution, which defines a D10
2.279 μm of diameter, 6.277 μm of a D50 partial size and 33.761 μm of a D90 partial size (being shown in table 1).B2 particle passes through about 2200
DEG C carbonization titanium dioxide and carbon particle made by.Polyolefin-based bottom, graft type polyolefin and the first and second titanium carbide granule contain
Scale is shown in table 2.The electrical characteristics result of the test sample of the concrete example 7 and 8 is shown in table 3.
<comparative example 1 (CE1)>
The production process and condition of the production process of comparative example 1 concrete example 1 similar with condition, in addition to the first and second titanium carbide
Except particle (for example, conductive filler) is replaced with nickel particle, and the component content in positive temperature coefficient polymer material is
Different.The electrical characteristics result of the test sample of comparative example 1 is shown in table 3.
<comparative example 2 (CE2)>
The production process of comparative example 2 and the production process and condition of condition analog example 1, are different in comparative example
2 conductive filler includes the nickel particle of 45wt% and the B1 particle of 45wt%.The electrical characteristics result of the test sample of comparative example 2
It is shown in table 3.
<comparative example 3 to 6 (CE3 to CE6)>
The production process of comparative example 3 to 6 and the production process and condition of condition analog example 1, in addition to comparative example 3 to 6
Conductive filler only include A1 particle and positive temperature coefficient polymer material component content it is different outer.The survey of comparative example 3 to 6
The electrical characteristics result of test agent is shown in table 3.
<comparative example 7 to 10 (CE7 to CE10)>
The production process and condition of the production process of comparative example 7 to 10 and condition analog example 1, in addition to comparative example 7 to
10 conductive filler only includes outside the component content difference of B1 particle and positive temperature coefficient polymer material.Comparative example 7 to 10
The electrical characteristics result of test sample be shown in table 3.
<comparative example 11 and 12 (CE11 and CE12)>
The production process of comparative example 11 and 12 and the production process of condition analog example 7 and 8 and condition, difference are in
Contain in the composition that the conductive filler of comparative example 11 and 12 includes B1 particle, B2 particle and its positive temperature coefficient polymer material
Amount is different.The electrical characteristics result of the test sample of comparative example 11 and 12 is shown in table 3.
<comparative example 13 and 14 (CE13 and CE14)>
The production process and condition of the production process of comparative example 13 and 14 concrete example 3 and 4 similar with condition.Its difference is in
In the conductive filler of comparative example 13 and 14 include A1 particle and first titanium carbide granule of second type (hereinafter referred to as A2 particle).
A2 particle has one 4.4 μm of average Fei Shi Microtraps partial size and 0.8% residual oxygen content (being shown in table 1).A2 particle also has
One 3.717 μm of D10 partial size, 10.54 μm of a D50 partial size and 39.26 μm of a D90 partial size (being shown in table 1).A2 particle by
Made by about 1850 DEG C of carbonization titanium dioxide and carbon particle.The electrical characteristics result of the test sample of comparative example 13 and 14 is shown in table
3。
<comparative example 15 and 16 (CE15 and CE16)>
The production process of comparative example 15 and 16 and the production process and condition of condition analog example 13 and 14.It does not exist together
The conductive filler for being comparative example 15 and 16 includes B1 particle and and A2 particle.The electricity of the test sample of comparative example 15 and 16 is special
Property result is shown in table 3.
<comparative example 17 and 18 (CE17 and CE18)>
The production process of comparative example 17 and 18 and the production process and condition of condition analog example 13 and 14.It does not exist together
The conductive filler for being comparative example 17 and 18 includes B2 particle and and A2 particle.The electricity of the test sample of comparative example 17 and 18 is special
Property result is shown in table 3.
Table 1
|
A1 |
A2 |
B1 |
B2 |
Average Fei Shi Microtraps partial size (μm) |
1.35 |
4.4 |
2.65 |
3.1 |
D10(μm) |
1.405 |
3.717 |
1.663 |
2.279 |
D50(μm) |
3.8 |
10.54 |
4.585 |
6.277 |
D90(μm) |
11.79 |
39.26 |
22.371 |
33.761 |
Residual oxygen content (%) |
0.9 |
0.8 |
0.2 |
0.2 |
Table 2
<test result>
[resistance value stability test]
The copper foil that one nickel thin slice is soldered to the test sample of the concrete example 1 to 8 and comparative example 1 to 18 (has resistance
Value Rc) to form a testing element.The resistance value (Rd) of the testing element is measured.One resistance increment rate (Rcd) is defined as
(Rd-Rc)/Rc × 100%.The result of resistance value stability test is shown in table 3.
Table 3
As a result the testing element resistance value and resistance increment rate for indicating the concrete example 1 to 8 are lower than the comparative example 1 to 18
Testing element resistance value and resistance increment rate.
[durability test]
Have one to switch within every 60 seconds in offer one ten test samples of the concrete example 1 to 8 and comparative example 1 to 18
The electric energy that the numerical value of open and close is 6Vdc/10A carries out a durability test, to determine resistance change rate (Rf/Ri) and institute
State the percent of pass of test sample, wherein Rf and Ri respectively indicate the test sample before durability test with rear resistance value.Table 4
Indicate that concrete example 1 to 8 has 100% percent of pass, and comparative example 1 and 2 and comparative example 8 to 18 have passing through less than 100%
Rate.In addition to this, the resistance change rate of concrete example 1 to 8 is less than the resistance change of comparative example 3 to 18.
Table 4
Contain first carbon in the positive temperature coefficient polymer material of PTC circuit protection element of the present invention
Change titanium particle and second titanium carbide granule, and then improve the electrical stability of PTC circuit protection element of the present invention,
Therefore the purpose of the present invention can be reached really.