A kind of high temperature resistant melt-blown non-woven material and preparation method thereof
Technical field
The present invention relates to the nonwoven material field, particularly relate to a kind of resistant to elevated temperatures melt-blown non-woven material and this preparation methods.
Background technology
Polypropylene melt-blown method nonwoven material is because fibre diameter is thin, specific area is big, hole is little, voidage is high, extremely is fit to be used as liquid or gas high efficiency filter material, and is that people accept widely and are familiar with along with the popular of SARS, H1N1 influenza.
Polypropylene melt-blown method nonwoven material processes by melt blown technology.The meltblown nonwoven techniques is that polymer directly becomes a kind of in the net non-weaving cloth technology, and its adopts high velocity, hot air that filament is stretched, and is directly made a kind of non-weaving cloth processing technology of superfine fibre or product by polymer or resin one-step method.Its concrete technological process is as follows:
Section feeds → melt extrudes → fiber formation → static electret → fiber cooling → one-tenth net → bonding (reinforcing) → ballingup
The section feeding: polypropylene chip is introduced into hopper, mixes with other additives (cooling masterbatch), is delivered into extruder;
Melt extrude: at the feed end of extruder, polypropylene chip and other additives etc. must mix by raw material, after fully stirring, enter Luo bar extruder, be heated as melt and through filter melt sent into spinnerets by measuring pump at last, in melt-blown process, general extruder also borrows its shear action and thermal degradation to reduce polymer molecular weight;
Fiber forms: will pass through distribution system through the cleaning melt that filters, send into every group of spinnerets more equably, make the extrusion capacity unanimity of each spinneret orifice, plate design and general chemical spinning are torn in the spray of melt-blown non-woven material, the filature fleece formation non-weaving cloth is different, its spinneret orifice must be arranged in line, both sides then have the spray groove of high velocity air up and down, and being used for the drawing-off melt becomes fiber;
Static electret: under molten condition, apply certain electrostatic field, make fiber have static;
The fiber cooling: the air at room temperature a large amount of in the spinnerets both sides are inhaled into simultaneously, mix with the thermal air current that contains superfine fibre, make the polypropylene fibre cooling, the superfine fibre of molten state thereby cooling curing;
Become net: under the state of net bottom negative pressure, thermal current sprays to into lace curtaining with the superfine fibre that the working air current band that the room temperature air-flow mixes mutually wherein, be condensed into net, by the mixed airflow band to the superfine fibre that becomes lace curtaining basically with mixed and disorderly distributions in air-flow, wherein some fiber has a spot of entanglement each other, under proper technical conditions, fibre deposition still has Yu Wen on the net the time, and is very soft, toughness, so the part fiber produces cohesive action in the fibre web;
Bonding (reinforcing): self cohering of fibre web has more fluffy structure, good air retention or voidage.
Ballingup: before coiling, the burr on fusion spray cloth both sides are cut.
Generally below 120 degree, when being higher than this temperature applications, its heat resistance can't reach requirement for the polypropylene melt-blown method nonwoven material that routine obtains, its application of temperature.
Vermiculite is a kind of natural, nontoxic mineral matter, and dilatable mineral belong to silicate under high temperature action.The chemical formula of vermiculite is Mg
x(H
2O) { Mg
3-x[AlSiO
3O
10] (OH)
2, be a kind of secondary metamorphic mineral of water aluminosilicate that contains magnesium, be similar to mica outward, form through hydrothermal alteration effect or weathering by black (gold) mica usually, be the deflection shape when expanding because of its dehydration of being heated, form exactly likes leech, so claim vermiculite.Vermiculite has high temperature dilatancy, cation exchange, adsorptivity, water imbibition, sound insulation, thermal insulation, fire resistance.Vermiculite has been widely applied to fields such as building, metallurgy, oil, shipbuilding, environmental protection, insulation, heat insulation, insulation, energy-conservation, gardening.The animal husbandry aspect: expanded vermiculite has unique structural property and surface nature, and nontoxic, aseptic and chemical inertness, can be used as carrier, adsorbent, sticking agent, and feed addictive.
Summary of the invention
The objective of the invention is at the deficiencies in the prior art, a kind of melt-blown non-woven material with resistance to elevated temperatures and filtration efficiency is provided.
Another object of the present invention is to provide the preparation method of above-mentioned melt-blown non-woven material.
For achieving the above object, the present invention has adopted following technical scheme:
The invention discloses a kind of high temperature resistant melt-blown non-woven material, described material contains polypropylene fibre, contains the vermiculite powder in the described polypropylene fibre.
The particle diameter of described vermiculite powder is a nano-micro level.
In the preferred embodiment of the present invention, the particle diameter of described vermiculite powder is 10%~30% of a polypropylene superfine fiber fineness.
The fineness of described polypropylene fibre is generally 300nm~5 μ m.
Preferably, the mass percentage content of described vermiculite powder in described material is 3%~15%.
The grammes per square metre of described melt-blown non-woven material is 20~50g/m
2
Described polypropylene melt index is 800g/10min~1800g/10min.
The present invention further discloses the preparation method of described high temperature resistant melt-blown non-woven material, described method is fully mixed polypropylene with the vermiculite powder before being included in fiber formation, and common spinning.
Owing to adopted above technical scheme, the beneficial effect that the present invention is possessed is:
The present invention is added in the polypropylene melt-blown high efficiency filter material by vermiculite being received micro-powder, can obtain the resistant to elevated temperatures high efficiency filter material that melts and sprays.The polypropylene melt-blown high efficiency filter material that adopts this technical scheme to make, its filter efficiency reaches more than 95%, the projection that similar bubble is arranged on this melts and sprays the superfine fibre of high efficiency filter material, when high temperature used, vaporization had reduced polyacrylic temperature thereby the crystallization water in the bubble absorbs heat, and because the effect of bubble, increased specific area, improved filter efficiency, also improved heat resistance, heat resisting temperature is above 140 ℃.
The specific embodiment
The present invention aims to provide a kind of containing and receives the polypropylene melt-blown high efficiency filter material of micron vermiculite powder, this material is to sneak into a certain proportion of micron vermiculite powder of receiving in spinning process, in the melt-out spinning process, the crystallization water vaporization of vermiculite powder, on the superfine fibre of polypropylene melt blown non-woven fabric, form the projection of similar bubble one by one, after the cooling, again form the crystallization water, in the high temperature use afterwards, external heat at first will make the crystallization water vaporization in the filtering material, and this has improved the heat resistance of polypropylene melt-blown high efficiency filter material.Polypropylene melt-blown nonwoven fabric material grammes per square metre 20-50g/m of the present invention
2, its filter efficiency reaches more than 95%.
In order to guarantee effective mechanical strength, the mass percentage content of vermiculite powder should be in the scope of 3%-15%, adjust content according to serviceability temperature, in above-mentioned scope, the vermiculite power body burden is high more, and heat-resisting quantity is good more, but along with the increase of content, the physical property of product can great changes have taken place, powerful can the reduction.
In concrete embodiment of the present invention, be with melt index be 800g/10min~1800g/10min isotactic polypropylene section with receive micron vermiculite powder and be (85-97) with ratio: mass ratio (15-3) mixes, and carries out production and processing according to the technology of melt blown non-woven.In the screw rod squeezer, because internal pressure is big, do not produce bubble, but one goes out spinnerets, because ambient pressure diminishes rapidly, the pressure height of the water vapour around the vermiculite powder causes having the local of vermiculite powder to bubble rapidly, then along with the cooling of fiber, steam becomes the crystallization water again, bubble can dwindle, and forms more minute bubbles of irregular status, and producing grammes per square metre is 20-50g/m
2Polypropylene melt-blown method non-weaving cloth.Above-mentioned used melt index is the above isotactic polypropylene section of 800g/10min~1800g/10min, is the raw material specification commonly used of polypropylene melt-blown nonwoven fabric, for other conventional raw materials, equally also is applicable to the present invention.The used micron vermiculite powder of receiving, its particle diameter can both reach the effect of expectation usually as long as in the nano-micro level scope.But preferable particle size is 10~30% of a fibre fineness, more preferably about 1/5.And the superfine fibre fineness of common polypropylene melt blown non-woven material is about 300 nanometers to 5 micron.
The above-mentioned polypropylene melt-blown high efficiency filter material for preparing, its filter efficiency reaches more than 95%, the projection that similar bubble is arranged on this melts and sprays the superfine fibre of high efficiency filter material, when high temperature uses, vaporization has reduced polyacrylic temperature thereby the crystallization water in the bubble absorbs heat, and because the effect of bubble has increased specific area, improve filter efficiency, improved the heat resistance of material simultaneously.
The present invention is described in further detail below by specific embodiment.
Embodiment 1:
Before spinning, with melt index is that isotactic polypropylene section more than the 1200g/10min is that 90: 10 mass ratio mixes with receiving micron vermiculite powder with ratio, carry out production and processing according to the technology of melt blown non-woven then, in the screw rod squeezer, because internal pressure is big, do not produce bubble, but one goes out spinnerets, because ambient pressure diminishes the pressure height of the water vapour around the vermiculite powder rapidly, cause having the local of vermiculite powder to bubble rapidly, along with the cooling of fiber, steam becomes the crystallization water again then, and bubble can dwindle, form more minute bubbles of irregular status, producing grammes per square metre is 35g/m
2Polypropylene melt-blown method non-weaving cloth.Fibre fineness is about 1 μ m, and the average grain diameter of used vermiculite powder is about 200nm.
After testing, the filter efficiency of this material reaches 99.99%, and the heatproof temperature is 140 degree, can be used for automobile danger gas and filter.
Embodiment 2:
With melt index is that isotactic polypropylene section more than the 1000g/10min is that 85: 15 mass ratio mixes with receiving micron vermiculite powder with ratio, technology according to melt blown non-woven is carried out production and processing, in the screw rod squeezer, because internal pressure is big, do not produce bubble, but one goes out spinnerets, because ambient pressure diminishes rapidly, the pressure height of the water vapour around the vermiculite powder causes having the local of vermiculite powder to bubble rapidly, then along with the cooling of fiber, steam becomes the crystallization water again, bubble can dwindle, and forms more minute bubbles of irregular status, and producing grammes per square metre is 40g/m
2Polypropylene melt-blown method non-weaving cloth.Fibre fineness is about 3 μ m, and the average grain diameter of used vermiculite powder is about 0.6 μ m.
The filter efficiency of this material reaches more than 99.99%, and the heatproof temperature is 150 degree, and being combined with each other with other materials is used as bag filter.
Above content be in conjunction with concrete embodiment to further describing that the present invention did, can not assert that concrete enforcement of the present invention is confined to these explanations.For the general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, can also make some simple deduction or replace, all should be considered as belonging to protection scope of the present invention.