CN105367901A - Glass fiber-reinforced polypropylene composite material and LFT-D preparation method thereof - Google Patents

Abstract

The present invention provides a glass fiber-reinforced polypropylene composite material and an LFT-D preparation method thereof. The raw materials thereof comprise: 40-60% of polypropylene, 10-30% of polyethylene, 10-45% of glass fiber, 0.5-5% of a compatilizer, 0.5-3% of a shrinkage inhibitor, 1-5% of a coupling agent and 0.5-3% of an internal lubricant. The preparation method comprises: conducting screw mixing in an LFT-D production line according to the ratio of the raw materials, wherein the mixing temperature is 190-220 DEG C and the mixing rotational rate is 100-200 r/min; then extruding the raw materials and transporting the raw materials in an insulating manner, wherein the insulation temperature is 150-180 DEG C; then performing compression molding, wherein the mould temperature is 20 DEG C-60 DEG C, the pressure is 1000-2000 ton per square meter pf a mould projection area and the pressure maintaining time is 20s per millimeter in thickness; and finally ejecting and taking the product, wherein the ejection speed is 5-20 mm/s. The composite material and the preparation method solve the problems that the existing product is rough in surface and obvious in shrinking traces, and the quality of a polypropylene composite material is greatly improved.

Description

A kind of glass fiber reinforced polypropylene composite material and LFT-D preparation method thereof

[technical field]

The present invention relates to a kind of glass fiber reinforced polypropylene composite material and LFT-D preparation method thereof.

[background technology]

LFT-D (Long-FiberReinforceThermoplasticDirect) Chinese is translated into direct-on-line long fiber reinforcement thermoplastic composite material, the key factor that it is different from GMT and LFT-G is that work in-process step has been removed, also more flexible in the selection of material.In LFT-D technology, the not only content of fiber and length, and also its matrix polymer also directly can adjust to the requirement of final parts.The typical technique of LFT-D is that polymer base particles and additive are transported in the combination of gravimetric analysis feeder unit, and this unit guarantees suitable mixing according to the mechanical property requirements of parts.Enter the plasticizing of twin screw counting machine through mixed raw material, its melting compound forms the polymeric film of similar waterfall by a sheeting die, directly enters the opening part of twin-screw mixer extruding machine.Fibre glass roving then by particular to creel.Through preheating, supervisor is disperseed to be introduced in the top of polymeric film, converge with film and together enter into Bitruder, cut rove by screw rod, and in the middle of the polymkeric substance that they are mildly mixed into fritting, then directly send in compacting tool set shaping.

In the automotive industry, due to long fiber reinforced thermoplastic composites not only density low (1.1 ~ 1.4g/cm3), and there is good mechanical property, its tensile strength, Young's modulus, impelling strength, thermotolerance and creep resistance are all obviously better than the thermoplastics of short fiber reinforced, particularly its shock resistance is high and be usually designed to structural part and the half hitch component of automobile, as: front, rear energy-absorbing bumper, front-end module skeleton, instrument desk skeleton, before, back seat skeleton, door module skeleton, tyre-well, cell box and body bottom backplate and silencing hood etc.In recent years, back holding door inner structure plate and the step plate of going back some automobile select LFT-D material to make, and its application obtains constantly innovation and expands.

Deaeration turner is out of trade, and LFT-D mould pressing technology is also widely used in each industry such as machinery, building, sports and amusement, electric and electronic, logistics and gardening, civil area.

Surface irregularity in existing glass fiber reinforced polypropylene composite material, cannot be applied to the problem of the production of the high product of effects on surface requirement, and in addition, the glass fibre/polypropylene articles its surface compressed trace adopting LFT-D technology to prepare is obvious, affects product quality.

[summary of the invention]

One of the technical problem to be solved in the present invention, is to provide a kind of glass fiber reinforced polypropylene composite material, which solves currently available products surface irregularity, shrinks the problems such as trace is obvious, substantially increase the quality of polypropylene composite material.

The present invention realizes one of above-mentioned technical problem like this:

A kind of glass fiber reinforced polypropylene composite material, calculate by massfraction, its raw material is composed as follows:

Polypropylene: 40-60%, polyethylene 10-30%, glass fibre 10-45%, compatilizer 0.5-5%, contraction inhibitor 0.5-3%, coupling agent 1-5%, internal lubricant 0.5-3%.

The technical problem to be solved in the present invention two, is the LFT-D preparation method providing a kind of glass fiber reinforced polypropylene composite material, which solves currently available products surface irregularity, shrinks the problems such as trace is obvious, substantially increase the quality of polypropylene composite material.

The present invention realizes above-mentioned technical problem two like this:

A LFT-D preparation method for glass fiber reinforced polypropylene composite material, calculates by massfraction, the raw material of matrix material composition and proportioning as follows:

Polypropylene: 40-60%, polyethylene 10-30%, glass fibre 10-45%, compatilizer 0.5-5%, contraction inhibitor 0.5-3%, coupling agent 1-5%, internal lubricant 0.5-3%;

First produce in line at LFT-D and carry out screw mixing according to described proportioning raw materials, melting temperature 190-220 DEG C, mixing rotating speed 100-200r/min; Then extrude and be incubated conveying, holding temperature 150-180 DEG C; Then compression molding, die temperature 20 DEG C-60 DEG C, pressure: mould shadow area every square metre of 1000-2000 ton, dwell time: every mm of thickness 20s; Finally eject and get product, eject speed 5-20mm/s.

Tool of the present invention has the following advantages:

1. by introducing highly polished polyethylene in glass fibre and polypropylene composite materials system, product surface smooth finish is improved; 2. by adding contraction inhibitor and internal lubricant, product is made to show to there is not contraction trace; 3. produce line compound by glass fibre, polypropylene, polyethylene three at LFT-D, make the mechanical property of composite product high; 4. by introducing glass fibre, the shrinking percentage of the matrix material that itself and polypropylene, polyethylene alloy are formed is reduced to 0.2-0.8%.

[embodiment]

The present invention relates to a kind of glass fiber reinforced polypropylene composite material, calculate by massfraction, its raw material is composed as follows:

Polypropylene: 40-60%, polyethylene 10-30%, glass fibre 10-45%, compatilizer 0.5-5%, contraction inhibitor 0.5-3%, coupling agent 1-5%, internal lubricant 0.5-3%.

The invention still further relates to the LFT-D preparation method of above-mentioned a kind of glass fiber reinforced polypropylene composite material, specific as follows: first to produce in line at LFT-D and carry out screw mixing according to described proportioning raw materials, melting temperature 190-220 DEG C, mixing rotating speed 100-200r/min; Then extrude and be incubated conveying, holding temperature 150-180 DEG C; Then compression molding, die temperature 20 DEG C-60 DEG C, pressure: mould shadow area every square metre of 1000-2000 ton, dwell time: every mm of thickness 20s; Finally eject and get product, eject speed 5-20mm/s.

Below in conjunction with specific embodiment, the present invention is further illustrated.

Embodiment:

Automobile bottom backplate polypropylene, polyethylene/glass fibre produces the manufacture of line in LFT-D, and concrete formula, parameter and product test the results are shown in following table:

Table one: end backplate is filled a prescription

Starting material	Ratio
		Polypropylene	60
Polyethylene	20
		Glass fibre	20
Internal lubricant	1
		Compatilizer	1
Coupling agent	2
		Contraction inhibitor	2

Table two: end backplate fabrication process parameters

Project	Parameter
		End backplate size	1209mm×54mm
The main thickness of end backplate	1.5mm
		Extruder temperature	200℃
Screw speed	150r/min
		Holding temperature	160℃
Die temperature	Upper 50 DEG C/lower 40 DEG C
		Pressure	1200T
Dwell time	30s

Table three: end sheeting product is tested

Project	Result
		Apparent burr	Nothing
Apparent contraction trace	Nothing
		Shrinking percentage	0.5％
Tensile strength	54MPa
		Tensile modulus	3521MPa
Flexural strength	90MPa
		Modulus in flexure	4550MPa
Shock strength	56KJ/㎡

After sample shock test, batten does not all rupture completely, presents the toughness that it is higher.Therefore in surface quality, intensity, toughness, good performance is all shown.

Although the foregoing describe the specific embodiment of the present invention; but be familiar with those skilled in the art to be to be understood that; specific embodiment described by us is illustrative; instead of for the restriction to scope of the present invention; those of ordinary skill in the art, in the modification of the equivalence done according to spirit of the present invention and change, should be encompassed in scope that claim of the present invention protects.

Claims (2)

1. a glass fiber reinforced polypropylene composite material, is characterized in that: calculate by massfraction, its raw material is composed as follows:

Polypropylene: 40-60%, polyethylene 10-30%, glass fibre 10-45%, compatilizer 0.5-5%, contraction inhibitor 0.5-3%, coupling agent 1-5%, internal lubricant 0.5-3%.

2. a LFT-D preparation method for glass fiber reinforced polypropylene composite material, is characterized in that: calculate by massfraction, the raw material of matrix material composition and proportioning as follows:

Polypropylene: 40-60%, polyethylene 10-30%, glass fibre 10-45%, compatilizer 0.5-5%, contraction inhibitor 0.5-3%, coupling agent 1-5%, internal lubricant 0.5-3%;

First produce in line at LFT-D and carry out screw mixing according to described proportioning raw materials, melting temperature 190-220 DEG C, mixing rotating speed 100-200r/min; Then extrude and be incubated conveying, holding temperature 150-180 DEG C; Then compression molding, die temperature 20 DEG C-60 DEG C, pressure: mould shadow area every square metre of 1000-2000 ton, dwell time: every mm of thickness 20s; Finally eject and get product, eject speed 5-20mm/s.