Technical field
The invention belongs to polymer matrix composites field, relate to a kind of BMC polyester molding compound and its preparation method and application.
Background technology
Moulding compound mainly comprises BMC BMC (Bulk Molding Compound), is that eighties of last century is sent out the sixties Exhibition get up with the polymer matrix composites of glass fiber reinforcement.BMC polyester molding compound is due to its excellent mechanical performance and excellent Different electrical property and heat resistance, low-shrinkage and good processing characteristics, can meet the requirement to performance of the various product, the most extensively Generally for all trades and professions such as electrical equipment, instrument, automobile making, aviation, traffic, buildings.Conventional BMC is mainly with unsaturated polyester Ester resin, as matrix, is filled other materials, is reinforcing material with glass fibre, coordinates auxiliary material such as lower shrinkage to add simultaneously Agent, initiator, thickener, releasing agent etc. are made.More excellent in order to obtain performance, purposes widely BMC, the most several Over Nian, both at home and abroad the characteristic of primary raw material is all being studied by many research institutions and enterprise, the BMC that research and development are modified.
Along with the development of BMC, having penetrated into more field, the industry at boats and ships naval vessels is subject to more and more in recent years Many attention, ships and light boats navigate by water all the year round among rivers and lakes, deep-sea, ocean, expose to the sun and rain, and bubble salt loses, and working environment is extremely disliked Bad, therefore it is required that build ships and light boats material is water-fast, salt spray resistance, acid-alkali-corrosive-resisting, resistance to environmental aging etc..
Therefore, develop and a kind of have that to can tolerate the BMC polyester molding compound of adverse circumstances be the problem that this area needs solution badly.
Summary of the invention
For the deficiencies in the prior art, it is an object of the invention to provide a kind of BMC polyester molding compound and preparation method thereof And application.
For reaching this purpose, the present invention by the following technical solutions:
On the one hand, the present invention provides a kind of BMC polyester molding compound, and described BMC polyester molding compound is mainly by mass percent Following raw material prepares:
Preferably, described auxiliary agent includes curing agent, releasing agent, thickener, antioxidant and dispersant, described auxiliary agent each Composition mass percent shared by BMC polyester molding compound raw material is as follows:
As optimal technical scheme, BMC polyester molding compound of the present invention is mainly by the raw material that mass percent is following Prepare:
BMC polyester molding compound of the present invention is to add novel weatherability insatiable hunger in the agent structure of conventional material And polyester resin, weather resisteant shrinking agent, weather-proof color, and acid and alkali-resistance salt fog auxiliary agent, improve demoulding flatness, then coordinate With filler, the new polyester moulding compound that the auxiliary material such as alkali-free glass fibre and carbon fiber is made.This New-type mould plastics pole Big improve BMC moulding compound service life on boats and ships naval vessels, acid and alkali-resistance, salt fog performance than common BMC moulding compound Being enhanced about more than once, this material can keep again its original premium properties for a long time simultaneously.
Preferably, described weatherability unsaturated polyester resin is the unsaturated polyester resin of epoxy resin modification.
Preferably, the viscosity of described weatherability unsaturated polyester resin is 1400-1450mPa s, such as 1400mPa S, 1410mPa s, 1420mPa s, 1430mPa s, 1440mPa s or 1450mPa s.
Described weatherability unsaturated polyester resin has excellent wellability, the performance such as resistance to water, acidproof alkali salt.
Preferably, described weatherability low shrinkage additive is polystyrene, polymethyl methacrylate, polyvinyl acetate Or any one or the combination of at least two, preferably polystyrene in PET.
Weatherability low shrinkage additive of the present invention has superior contraction and controls, and superior coloring, lubricity is good.
Preferably, described packing material is the hydration oxygen of particle diameter 7-9 μm (such as 7 μm, 7.5 μm, 8 μm, 8.5 μm or 9 μm) Change aluminium and/or calcium carbonate powder.
Preferably, described hydrated alumina is hibbsite and/or monohydrate alumina.
Preferably, described fibrous material is the composite fibre of glass fibre and carbon fiber.
Preferably, described fibrous material is with alkali-free short glass fiber and chopped polyacrylonitrile carbon fiber as raw material, warp Cross pre-oxidation, carbonization and prepare.There is cyclisation crosslinking in the pre-oxidation stage in the chain structure of chopped fiber, forms heat-resisting trapezoidal knot Structure, carbonation stage conjugation forms carbon back face, and carbon back face length is big and ultimately forms graphite-like structure.
Fibrous material light specific gravity of the present invention, intensity is high, acid and alkali-resistance salt corrosion, antifatigue, abrasion performance.
Preferably, described weather-proof color be by 5-15% (such as 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% or 15%) weather-proof color toner and 85-95% (85%, 88%, 90%, 91%, 92%, 93%, 94% Or 95%) mixing of weatherability monomer-free unsaturated polyester resin mills the mill base made.
Preferably, described curing agent be purity be the peroxidized t-butyl perbenzoate of more than 98%；Its 10 hour half-life Temperature is 104 DEG C.
Preferably, described releasing agent be particle diameter 150-250 mesh (such as 150 mesh, 170 mesh, 190 mesh, 200 mesh, 220 mesh, 230 mesh, 240 mesh or 250 mesh) calcium stearate or zinc stearate.
Preferably, described thickener is liquid oxidation magnesium, calcium hydroxide or magnesium hydroxide, and liquid oxidation magnesium easily disperses, no Dust can be produced.Liquid oxidation magnesium can be by being commercially available, such as Luvatol MK35.
Preferably, described antioxidant is 2,6-di-t-butyl Pyrogentisinic Acid, double (3,5-di-tert-butyl-hydroxy phenyl) sulphur Any one or the combination of at least two in ether or three (2,4-di-tert-butyl-phenyl) phosphite ester；Preferably 2,6-di-t-butyl Pyrogentisinic Acid, it has good antioxidation, good compatibility, and under processing temperature, antioxidant itself is more stable.
Preferably, described dispersant is BYK-W-996 or BYK-9010, and it is the copolymer solution containing acidic-group, The mixture of surface reactive material and polymer, its can stable mode plastics, improve mobility, improve release property etc..
The BMC polyester molding compound of the present invention combines the advantage of each composition, and it is by cooperating, mutually between each composition Promote so that the BMC polyester molding compound obtained has the weatherability of excellence, and anti-swelling, freedom from cracking and ageing resistace all have bright Aobvious improving, shaping shrinkage rate is low, and heat distortion temperature is high, and bending strength is high, has good mechanical performance, excellent insulating properties with And anti-flammability etc..
In the present invention, described weatherability refers to material to expose to the open air under the weather conditions such as daylight, cold and hot, wind and rain to keep this Body physicochemical property does not changes.
In the present invention, in the raw material of described BMC polyester molding compound, each composition sum is 100%.
On the other hand, the invention provides the preparation method of BMC polyester molding compound as described in relation to the first aspect, described preparation Method comprises the following steps:
(1) unsaturated polyester resin, low shrinkage additive, dispersant and pigment are stirred；
(2) in the compound that step (1) obtains, add curing agent and antioxidant, stirring, then add packing material And releasing agent, continue stirring；
(3) adding thickener in the compound that step (2) obtains, stirring, the fibrous material then adding 5-10% stirs After mixing 5-10 minute (such as 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes or 10 minutes), add residual fiber material and continue Stirring, obtains described BMC polyester molding compound.
Preferably, the time of step (1) described stirring is 2-10 minute, such as 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 Minute, 7 minutes, 8 minutes, 9 minutes or 10 minutes.
Preferably, the time of step (2) described stirring is 3-10 minute, such as 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 Minute, 8 minutes, 9 minutes or 10 minutes.
Preferably, step (2) described continue stirring time be 20-40 minute, such as 20 minutes, 22 minutes, 25 minutes, 28 minutes, 30 minutes, 32 minutes, 35 minutes, 38 minutes or 40 minutes.
Preferably, the time of step (3) described stirring is 10-20 minute, such as 10 minutes, 12 minutes, 14 minutes, 15 points Clock, 16 minutes, 18 minutes or 20 minutes.
Preferably, step (3) described continue stirring time be 10-20 minute, such as 10 minutes, 12 minutes, 14 minutes, 15 minutes, 16 minutes, 18 minutes or 20 minutes.
Preferably, the preparation of described BMC polyester molding compound is carried out in kneading machine.
In the present invention by specific preparation technology as above so that each composition is sufficiently mixed uniformly, fills between each composition Tap is touched, and to reach to interact fully, such as, makes carbon fiber and glass fibre can be uniformly distributed among material, improves material The intensity of material can also be improved, it is achieved that the acid and alkali-resistance salt corrosion to polyester resin is modified, to poly-while the weatherability of material Ester resin hydrolytic-resistant modified, mixes enhancing modified etc. to the anticorrosive modification of pigment and carbon fiber with glass fibre.
On the other hand, the invention provides BMC polyester molding compound as described in relation to the first aspect in preparing weather resistant materials Application.The BMC polyester molding compound of the present invention can be used as weather resistant materials or for preparing weather resistant materials, for electrical equipment, In the every profession and trades such as instrument, automobile making, aviation, traffic, building.
Relative to prior art, the method have the advantages that
The BMC polyester molding compound of the present invention is by cooperating between each composition, mutually coordinated so that BMC polyester mould Plastics have the weatherability of excellence, and anti-swelling, the freedom from cracking of normal polyester moulding compound and ageing resistace are only 15 years, and this Anti-swelling, freedom from cracking and the ageing resistace of bright BMC polyester molding compound are 35 years, the low ＜ of shaping shrinkage rate 0.15%, Water absorption rate ＜ 0.2%, heat distortion temperature ＞ 240 DEG C, bending strength >=200MPa, there is good mechanical performance, insulation opposing ＞ 106Ω, proof voltage performance can reach 4-6KV/mm, and arc resistance >=100Sec, the ＞ of resistance to leakage property 300CTI, anti-flammability is permissible Arrive V0 level, high comprehensive performance, have a wide range of applications in fields such as electrical equipment, instrument, automobile making, aviation, traffic, buildings Prospect.
Detailed description of the invention
Technical scheme is further illustrated below by detailed description of the invention.Those skilled in the art should be bright , the only help of described embodiment understands the present invention, is not construed as the concrete restriction to the present invention.
Embodiment 1
In the present embodiment, the raw material that mass percent is following BMC polyester molding compound is prepared:
Described fibrous material is with alkali-free short glass fiber and chopped polyacrylonitrile carbon fiber as raw material, through pre-oxygen Change, carbonization and prepared glass fibre and the composite fibre of carbon fiber, described weatherability unsaturated polyester resin is epoxy resin Modified unsaturated polyester resin, described weatherability low shrinkage additive is polystyrene, and described packing material is particle diameter 7-9 μm Hydrated alumina, described weather-proof color is by 10% weather-proof color toner and 90% weatherability monomer-free unsaturated polyester (UP) tree Fat mixing is milled the mill base made, described curing agent be purity be the peroxidized t-butyl perbenzoate of more than 98%, the described demoulding Agent is the calcium stearate powder of particle diameter 150-250 mesh, and described thickener is liquid oxidation magnesium, and described antioxidant is 2,6-bis-uncle Butyl Pyrogentisinic Acid, described dispersant is BYK-W-996.
Preparation method is as follows:
(1) unsaturated polyester resin, low shrinkage additive, dispersant and pigment are stirred 2 minutes to stirring；
(2) in the compound that step (1) obtains, add curing agent and antioxidant, stir 3 minutes, then add filling Material and releasing agent, continue stirring 20 minutes；
(3) in the compound that step (2) obtains, add thickener, stir 20 minutes, then add the fibrous material of 5% After stirring 5 minutes, add residual fiber material and continue stirring 10 minutes, obtain described BMC polyester molding compound.
Embodiment 2
In the present embodiment, the raw material that mass percent is following BMC polyester molding compound is prepared:
Described fibrous material is with alkali-free short glass fiber and chopped polyacrylonitrile carbon fiber as raw material, through pre-oxygen Change, carbonization and prepared glass fibre and the composite fibre of carbon fiber, described weatherability unsaturated polyester resin is epoxy resin Modified unsaturated polyester resin, described weatherability low shrinkage additive is polystyrene, and described packing material is particle diameter 7-9 μm Hydrated alumina, described weather-proof color is by 10% weather-proof color toner and 90% weatherability monomer-free unsaturated polyester (UP) tree Fat mixing is milled the mill base made, described curing agent be purity be the peroxidized t-butyl perbenzoate of more than 98%, the described demoulding Agent is the zinc stearate of particle diameter 150-250 mesh, and described thickener is calcium hydroxide, and described antioxidant is 2,6-di-t-butyl pair Phenol, described dispersant is BYK-W-996.
Preparation method is as follows:
(1) unsaturated polyester resin, low shrinkage additive, dispersant and pigment are stirred 10 minutes to stirring；
(2) in the compound that step (1) obtains, add curing agent and antioxidant, stir 5 minutes, then add filling Material and releasing agent, continue stirring 30 minutes；
(3) in the compound that step (2) obtains, add thickener, stir 10 minutes, then add the undulation degree of 10% After material stirring 10 minutes, add residual fiber material and continue stirring 10 minutes, obtain described BMC polyester molding compound.
Embodiment 3
In the present embodiment, the raw material that mass percent is following BMC polyester molding compound is prepared:
Described fibrous material is with alkali-free short glass fiber and chopped polyacrylonitrile carbon fiber as raw material, through pre-oxygen Change, carbonization and prepared glass fibre and the composite fibre of carbon fiber, described weatherability unsaturated polyester resin is epoxy resin Modified unsaturated polyester resin, described weatherability low shrinkage additive is polystyrene, and described packing material is particle diameter 7-9 μm Hydrated alumina, described weather-proof color is by 10% weather-proof color toner and 90% weatherability monomer-free unsaturated polyester (UP) tree Fat mixing is milled the mill base made, described curing agent be purity be the peroxidized t-butyl perbenzoate of more than 98%, the described demoulding Agent is the calcium stearate powder of particle diameter 150-250 mesh, and described thickener is magnesium hydroxide, and described antioxidant is double (3,5-bis- Tert-butyl-hydroxy phenyl) thioether, described dispersant is BYK-9010.
Preparation method is as follows:
(1) unsaturated polyester resin, low shrinkage additive, dispersant and pigment are stirred 2 minutes to stirring；
(2) in the compound that step (1) obtains, add curing agent and antioxidant, stir 3 minutes, then add filling Material and releasing agent, continue stirring 40 minutes；
(3) in the compound that step (2) obtains, add thickener, stir 15 minutes, then add the fibrous material of 8% After stirring 10 minutes, add residual fiber material and continue stirring 15 minutes, obtain described BMC polyester molding compound.
Embodiment 4
In the present embodiment, the raw material that mass percent is following BMC polyester molding compound is prepared:
Described fibrous material is with alkali-free short glass fiber and chopped polyacrylonitrile carbon fiber as raw material, through pre-oxygen Change, carbonization and prepared glass fibre and the composite fibre of carbon fiber, described weatherability unsaturated polyester resin is epoxy resin Modified unsaturated polyester resin, described weatherability low shrinkage additive is polystyrene, and described packing material is particle diameter 7-9 μm Hydrated alumina, described weather-proof color is by 10% weather-proof color toner and 90% weatherability monomer-free unsaturated polyester (UP) tree Fat mixing is milled the mill base made, described curing agent be purity be the peroxidized t-butyl perbenzoate of more than 98%, the described demoulding Agent is the calcium stearate powder of particle diameter 150-250 mesh, and described thickener is liquid oxidation magnesium, and described antioxidant is three (2,4- Di-tert-butyl-phenyl) phosphite ester, described dispersant is BYK-W-996.
Preparation method is as follows:
(1) unsaturated polyester resin, low shrinkage additive, dispersant and pigment are stirred 5 minutes to stirring；
(2) in the compound that step (1) obtains, add curing agent and antioxidant, stir 5 minutes, then add filling Material and releasing agent, continue stirring 25 minutes；
(3) in the compound that step (2) obtains, add thickener, stir 15 minutes, then add the fibrous material of 5% After stirring 10 minutes, add residual fiber material and continue stirring 20 minutes, obtain described BMC polyester molding compound.
Embodiment 5
In the present embodiment, the raw material that mass percent is following BMC polyester molding compound is prepared:
Described fibrous material is with alkali-free short glass fiber and chopped polyacrylonitrile carbon fiber as raw material, through pre-oxygen Change, carbonization and prepared glass fibre and the composite fibre of carbon fiber, described weatherability unsaturated polyester resin is epoxy resin Modified unsaturated polyester resin, described weatherability low shrinkage additive is polystyrene, and described packing material is particle diameter 7-9 μm Hydrated alumina, described weather-proof color is by 10% weather-proof color toner and 90% weatherability monomer-free unsaturated polyester (UP) tree Fat mixing is milled the mill base made, described curing agent be purity be the peroxidized t-butyl perbenzoate of more than 98%, the described demoulding Agent is the calcium stearate powder of particle diameter 150-250 mesh, and described thickener is liquid oxidation magnesium, and described antioxidant is 2,6-bis-uncle Butyl Pyrogentisinic Acid, described dispersant is BYK-W-996.
Preparation method is as follows:
(1) unsaturated polyester resin, low shrinkage additive, dispersant and pigment are stirred 8 minutes to stirring；
(2) in the compound that step (1) obtains, add curing agent and antioxidant, stir 10 minutes, then add and fill out Fill material and releasing agent, continue stirring 20 minutes；
(3) in the compound that step (2) obtains, add thickener, stir 15 minutes, then add the fibrous material of 8% After stirring 8 minutes, add residual fiber material and continue stirring 20 minutes, obtain described BMC polyester molding compound.
Comparative example 1
This comparative example difference from Example 1 be only that do not use in the raw material preparing BMC polyester molding compound weather-proof Property unsaturated polyester resin, the consumption of packing material is 70.79%, and remaining raw material and raw material dosage are same as in Example 1, system Preparation Method and condition are the most same as in Example 1.
Comparative example 2
This comparative example difference from Example 1 be only that do not use in the raw material preparing BMC polyester molding compound weather-proof Property unsaturated polyester resin, the consumption of weatherability low shrinkage additive is 28%, remaining raw material and raw material dosage and embodiment 1 Identical, preparation method and condition are the most same as in Example 1.
Comparative example 3
This comparative example difference from Example 1 is only that the raw material weatherability preparing BMC polyester molding compound is unsaturated The consumption of polyester resin is 22%, and the consumption of packing material is 48.79%, remaining raw material and raw material dosage and embodiment 1 phase With, preparation method and condition are the most same as in Example 1.
Comparative example 4
This comparative example difference from Example 1 is only that the raw material weatherability preparing BMC polyester molding compound is unsaturated The consumption of polyester resin is 14%, and the consumption of packing material is 56.79%, remaining raw material and raw material dosage and embodiment 1 phase With, preparation method and condition are the most same as in Example 1.
Comparative example 5
This comparative example difference from Example 1 is only that and does not use fiber in the raw material preparing BMC polyester molding compound Material, the consumption of packing material is 66.79%, and remaining raw material and raw material dosage are same as in Example 1, preparation method and bar Part is the most same as in Example 1.
Comparative example 6
This comparative example difference from Example 1 is only that in the raw material preparing BMC polyester molding compound use undulation degree Material is glass fibre, and consumption is 14%, and remaining raw material and raw material dosage are same as in Example 1, and preparation method and condition are equal Same as in Example 1.
Comparative example 7
This comparative example difference from Example 1 is only that in the raw material preparing BMC polyester molding compound the fiber used The consumption of material is 13%, and the consumption of packing material is 53.79%, and remaining raw material and raw material dosage are same as in Example 1, system Preparation Method and condition are the most same as in Example 1.
Comparative example 8
This comparative example difference from Example 1 is only that in the raw material preparing BMC polyester molding compound the fiber used The consumption of material is 19%, and the consumption of packing material is 47.79%, and remaining raw material and raw material dosage are same as in Example 1, system Preparation Method and condition are the most same as in Example 1.
Comparative example 9
This comparative example difference from Example 1 be only that do not use in the raw material preparing BMC polyester molding compound weather-proof Property pigment, the consumption of packing material is 55.79%, and remaining raw material and raw material dosage are same as in Example 1, preparation method and Condition is the most same as in Example 1.
Comparative example 10
This comparative example difference from Example 1 be only that do not use in the raw material preparing BMC polyester molding compound weather-proof Property pigment, the consumption of weatherability unsaturated polyester resin is 21%, and remaining raw material and raw material dosage are same as in Example 1, system Preparation Method and condition are the most same as in Example 1.
Comparative example 11
This comparative example difference from Example 1 be only that do not use in the raw material preparing BMC polyester molding compound weather-proof Property pigment, the consumption of weatherability low shrinkage additive is 13%, and remaining raw material and raw material dosage are same as in Example 1, preparation Method and condition are the most same as in Example 1.
Comparative example 12
This comparative example difference from Example 1 is only that in the raw material preparing BMC polyester molding compound the weather-proof of use The consumption of property pigment is 4%, and the consumption of packing material is 51.79%, and remaining raw material and raw material dosage are same as in Example 1, Preparation method and condition are the most same as in Example 1.
Comparative example 13
This comparative example difference from Example 1 is only that in the raw material preparing BMC polyester molding compound the weather-proof of use The consumption of property pigment is 1%, and the consumption of packing material is 54.79%, and remaining raw material and raw material dosage are same as in Example 1, Preparation method and condition are the most same as in Example 1.
BMC polyester molding compound embodiment 1-5 prepared (is added by ordinary resin, lower shrinkage with normal polyester moulding compound Agent and pigment prepare) carry out anti-swelling, freedom from cracking and ageing resistace test, result is as shown in table 1.
Table 1
The BMC polyester molding compound preparing embodiment 1-5 and comparative example 1-13 carries out performance test, testing standard And result is as shown in Table 2-4.
Table 2
Table 3
Table 4
By the test result of table 1 it can be seen that BMC polyester molding compound prepared by the present invention has the weatherability of excellence, often Anti-swelling, freedom from cracking and the ageing resistace of rule polyester molding compound are only 15 years, and the BMC polyester molding compound of the present invention is anti-molten Swollen, freedom from cracking and ageing resistace are 35 years.
By the test result of table 2-4 it can be seen that the BMC polyester molding compound of the present invention is by the phase interworking between each composition Close, mutually coordinated so that the low ＜ of shaping shrinkage rate 0.15% of BMC polyester molding compound, water absorption rate ＜ 0.2%, heat distortion temperature ＞ 240 DEG C, bending strength >=200MPa, have good mechanical performance, insulation opposing ＞ 106Ω, proof voltage performance can reach 4-6KV/mm, arc resistance >=100Sec, the ＞ of resistance to leakage property 300CTI, anti-flammability can arrive V0 level, high comprehensive performance, and When not using weatherability unsaturated polyester resin or weather-proof color in preparing raw material at it, its various aspects of performance the most under Fall, and by comparative example 1, comparative example 2 with the contrast of embodiment 1 it can be seen that weatherability unsaturated polyester resin and weather-proof Property low shrinkage additive promote BMC polyester molding compound various aspects of performance improvement on there is coordinative role, pass through comparative example 9, the contrast of comparative example 10 and comparative example 11 and embodiment 1 is it can be seen that weather-proof color, weatherability unsaturated polyester (UP) tree Fat, weatherability low shrinkage additive have coordinative role in the improvement of various aspects of performance promoting BMC polyester molding compound, and When each Ingredient Amount too much or very few time (such as comparative example 3-4, comparative example 11-12), its each side to BMC polyester molding compound The improvement of performance is not very notable, additionally, fibrous material used by the present invention is the composite fibre of glass fibre and carbon fiber, is With alkali-free short glass fiber and chopped polyacrylonitrile carbon fiber as raw material, preparing through pre-oxidation, carbonization, it is to raising The mechanical performance of BMC polyester molding compound and promote that the performance of each side has and significantly affect, when being changed to common glass During fiber (comparative example 6), the mechanical performance of BMC polyester molding compound is had a significant impact by it.
Applicant states, the present invention illustrates BMC polyester molding compound and the preparation side thereof of the present invention by above-described embodiment Method and application, but the invention is not limited in above-described embodiment, i.e. do not mean that the present invention has to rely on above-described embodiment ability Implement.Person of ordinary skill in the field it will be clearly understood that any improvement in the present invention, raw material each to product of the present invention etc. Effect is replaced and the interpolation of auxiliary element, concrete way choice etc., within the scope of all falling within protection scope of the present invention and disclosure.
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