CN103538136A - Polylactic acid composite board and preparation method thereof - Google Patents

Abstract

The invention discloses a polylactic acid composite board made of polylactic acid and hemp-based fibers, wherein the polylactic acid accounts for 25-39% of the composite board. The hemp-based fibers are mixtures of hemp fibers and one or more of bamboo fibers, wood fibers and palm fibers, wherein the hemp fibers account for 51-99% of the hemp-based fibers, and the hemp fibers are one of jute fibers, ramie fibers, sisal fibers and linen fibers or mixture of more of the four. The polylactic acid composite board has the advantages that board rigidity and tensile property are controlled by adjusting proportion of various fibers; use amount of high-cost polylactic acid can be adjusted, and the less the polylactic acid is used, the lower the material cost is; the board contains only the polylactic acid and natural fibers, no petroleum-based materials are contained, so that the board is non-toxic, odorless, nonvolatile, and completely degradable; no environmental pollution is created during manufacturing, use and after use of the board.

Description

A kind of PLA composite board and preparation method thereof

Technical field

The invention belongs to PLA and replace the application that petroleum base resin is produced melting wholly-degradable environment protection type composite fibre sheet material, reduced the use amount of expensive PLA, be specifically related to a kind of PLA composite board and preparation method thereof.

Background technology

Thermoplastic sheet refers to the sheet material after heating with plasticity, can manufacture the part of various shapes after heating with mould compacting again.Thermoplastic sheet application is very extensive, as the inner decorative ceiling plate in automobile, and interior trim gusset plate, clothing frame plate, the various special-shaped sheet materials in field such as luggage case trim panel and furniture, building, decoration etc.

Thermoplastic sheet mostly adopts petroleum base thermoplastic fibre and string is compound makes, as PP hemp fibre board, and PP glass mat etc.

Notification number is that the patent of CN203093190U discloses a kind of compound numb felt plate, forms: ground floor is bottom by four layers, and composition is polyster fibre; The 3rd layer is intermediate layer, by flaxen fiber and polypropylene fiber, is mixed; The 4th layer is superficial layer, and composition is macromolecule membrane; It is characterized in that: the second layer between described ground floor and the 3rd layer is coconut palm the third fiber.

Notification number is that the patent of CN200957680 discloses a kind of compound numb felt plate, mainly flaxen fiber, consists of, and it is characterized in that: the structure of product forms by three layers, and ground floor is bottom, and Main Ingredients and Appearance is polyster fibre; The second layer is intermediate layer, and Main Ingredients and Appearance is flaxen fiber and polypropylene fiber; The 3rd layer is superficial layer, and Main Ingredients and Appearance is polyster fibre and polypropylene fiber.

Notification number is that the patent of CN102294853A discloses a kind of Hamburg type fibrilia plate and preparation method thereof: it comprises (3) three layers of surface layer (1), flaxen fiber carpet veneer (2) and bottoms, and described surface layer (1) and bottom (3) are acupuncture nonwoven layer of cloth; Each component and the quality proportioning thereof of described needle punched non-woven fabrics are as follows: polypropylene fiber 40-60%, 4080 fiber 8-20%, polyster fibre 30-50%; Each component and the quality proportioning thereof of described bast fibre felt are as follows: monofilament and flaxen fiber 10-30%, polyster fibre 30-40%, polypropylene fiber 40-50%.First step during preparation: prepare needle punched non-woven fabrics; Second step: making one side is that needle punched non-woven fabrics, one side are the composite base material semi-finished product of bast fibre felt; The 3rd step, one-step mould is made finished product.

A large amount of composites that adopt petroleum base thermoplastic fibre or glass fibre to produce can produce serious problem of environmental pollution.PLA can derive from the plants such as corn, cassava, has Wholly-degradable, free from environmental pollution.Useful PLA replaces petroleum base resin to be compounded to form sheet material with natural plant fibre, and its compound method has determined structure and the characteristic of sheet material, has also determined the factors such as the efficiency of suitability for industrialized production and cost.

Notification number is the preparation method that the patent of CN101691054B discloses a kind of polylactic-acid-base linen fiber composite plates, its step is to pulverize with pulverizer powder-type and the corpuscular PLA that polylactic resin obtains, the method that adopts textile type flaxen fiber to lay layer by layer, utilizes mechanical property, thermoplasticity, fibre forming property, the transparency advantages of higher that PLA is good to make polylactic-acid-base linen fiber composite plates by hot press forming technology.

Foregoing invention have no can industrial high efficiency rate by powder-type and corpuscular PLA uniform spreading the method between textile type flaxen fiber layer, the adhesion between PLA and textile type flaxen fiber layer has no the expression method of firm reliability simultaneously.

Notification number is that the patent of CN101691045A discloses a kind of acid fiber by polylactic and flaxen fiber mixed plate and production method thereof.This flaxen fiber composition of inventing in described sheet material is single, not containing other fibers, the property regulation narrow range such as the rigidity of such sheet material and hot strength, the scope of application of sheet material is not wide, also cannot be by regulating the formation of fiber reduce the use amount of expensive PLA, make the material cost of sheet material occupy high-leveled and difficult under; This invents employing treatment fluid in described production method, and that fibrofelt is soaked to the method program of drying is again many, and cost is high.

Summary of the invention

In order to overcome above technical problem, the invention provides a kind of PLA composite board and preparation method thereof.

The technical solution adopted for the present invention to solve the technical problems is, a kind of PLA composite board, by PLA and numb base fiber, formed, the quality accounting of wherein said PLA is 25-39.5%, described numb base fiber is by one or more mixtures that form of flaxen fiber and bamboo fibre, wood-fibred, three kinds of fibers of monkey grass, and wherein the quality accounting of flaxen fiber is 51%-99%; Described flaxen fiber is one or more the mixture in tossa, ramee, sisal fiber, flax fiber;

A preparation method for PLA composite board, specifically comprises the steps:

A: one or more of flaxen fiber and bamboo fibre, wood-fibred, three kinds of fibers of monkey grass are mixed to form to numb base fiber;

B: PLA is spun into polylactic acid short-fiber;

C: polylactic acid short-fiber is mixed with numb base fiber and make composite fibrofelt;

D: to composite fibrofelt surface spraying treatment fluid;

E: finally heat composite fibrofelt and suppress and can make sheet material by the mode that roll-in or plate are pressed.

Treatment fluid in above-mentioned steps D is one or more the mixture in fire retardant, antiseptic, antioxidant, so that fiberboard reaches antibiotic, fire-retardant serviceability.

The beneficial effect that the present invention produces is, the present invention can meanwhile, can regulate the use amount of expensive PLA by regulating the accounting of various fibers to control rigidity and the tensile property of sheet material, and the use amount of PLA is lower, and the cost of material is lower.In addition, only have PLA and natural fiber in sheet material,, containing any petroleum base material, nonpoisonous and tasteless, non-volatility, does not have Wholly-degradable; When manufacturing, using and all free from environmental pollution after using.

Accompanying drawing explanation

Production technological process of the present invention as shown in the figure.

The specific embodiment

The equipment that embodiments of the present invention relate to is existing universal industrial equipment, is specially: vacuum drum drying machine, screw extruding melt spinning machine, drawing of fiber extruder, fibre cutting machine, carding machine, mixing willow (mixing), lapping machine, needing machine, tunnel type baking oven, closed baking oven, roll squeezer, plate pressing machine etc.

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

Embodiment 1:

The numb base fiber of the present embodiment is comprised of tossa, ramee, bamboo fibre, and its quality accounting is respectively: 80%, 15%, 5%; The quality accounting of PLA and numb base fiber is respectively 39%, 61%.

A, is mixed to form numb base fiber by flaxen fiber and bamboo fibre, and concrete steps are as follows:

A1: tossa, ramee, bamboo fibre are cut into respectively to short fiber the shredding respectively that length is 120mm, 100mm, 90mm;

A2: tossa, ramee, bamboo fibre that the ratio by 80%, 15%, 5% makes A1 step are sent into mixing willow and be mixed to form numb base fiber;

B, is spun into polylactic acid short-fiber by PLA, and concrete steps are as follows:

B1: PLA is carried out in vacuum drum drying machine to vacuum drum and be dried 8-48 hour to remove moisture, make its moisture content below 0.005%;

B2: by the PLA being dried by screw extruder melt spinning, more crooked through drawing-off, extruding, cut off and make polylactic acid short-fiber, concrete specification is fiber number 10-50dtex, length 30-120mm, number of bends is 0.2-1/mm;

C: polylactic acid short-fiber is mixed with numb base fiber and make composite fibrofelt;

Concrete steps are as follows:

C1, numb base fiber prepared by polylactic acid short-fiber prepared by B step and steps A is sent into sealing composite fibre room after mixing willow mixes by quality accounting 39%, 61%;

C2, sends into the composite fibre in composite fibre room after carding machine combing, and makes composite fibrofelt through the method for lapping, acupuncture.During lapping, according to requirements control width and the thickness of fibrofelt;

D: to composite fibrofelt surface spraying treatment fluid.This treatment fluid is one or more the mixture in fire retardant, antiseptic, antioxidant, and spray flux is controlled at 10-400g/m ²;

E: can make sheet material with the composite fibrofelt that the mode that roll-in or plate are pressed adds after hot pressing D step

(a) adopt roll-in mode, concrete steps are as follows:

Ea1: the composite fibrofelt after D step is sent into tunnel oven continuously, and the temperature of the entrance of tunnel oven, middle part, outlet is arranged to respectively 110-130 ± 5 °, 150-170 ± 5 °, 190-210 ± 5 ° according to the thin degree of felt; The speed of composite fibrofelt access tunnel baking oven is 10mm-200mm/s.

Ea2: suppress and can make sheet material send into roll squeezer from baking oven high temperature composite fibrofelt out.Roll-in speed is identical with Ea1 step;

Ea3: the size that roll squeezer plate cutting is out become to meet to instructions for use;

(b) adopt plate to press mode, concrete steps are as follows:

Eb1: the composite fibrofelt after D step is cut into required area on request;

Eb2: the composite fibrofelt of well cutting is sent into sealing baking oven, and the temperature in baking oven is arranged to 190-210 ± 5 ° according to the thin degree of felt;

After Eb3:1-5 minute, the composite fibrofelt in taking-up sealing baking oven is sent into trigger squeeze compacting can make sheet material;

Embodiment 2:

The ratio of numb base fiber is different as different from Example 1, and numb base fiber is comprised of tossa, ramee, bamboo dimension, and its quality accounting is respectively: 60%, 20%, 20%; The mass ratio of PLA and numb base fiber is with embodiment 1, and the mode of production is with embodiment 1.

Embodiment 3:

The quality accounting of different from embodiment 1 and 2 is PLA and numb base fiber is respectively 34%, 66%, and the formation of numb base fiber is tossa 60%, monkey grass 40%, and the mode of production is with embodiment 1.

The material accounting of above-mentioned 3 embodiment is different, and the performance of sheet material is also different, specifically as shown in table 1:

As can be seen from Table 1, due to the increase of bamboo fibre and ramee ratio, embodiment 2 has improved 15.6% than the hot strength of embodiment 1, but elongation at break has reduced by 26.9%, therefore embodiment 2 is applicable to do the internal hilar plate that degree of drawing is low, intensity is high, and embodiment 1 is applicable to hat rack.Embodiment 3 is owing to having adopted the monkey grass of higher proportion, its tensile property is increased substantially, applicable to doing ceiling, make the quality accounting of expensive PLA be down to 34% simultaneously, make the material cost of whole sheet material compare embodiment 1 or embodiment 2 has reduced by 15%.

Table 1

Claims (6)

1. a PLA composite board, it is characterized in that, by PLA and numb base fiber, formed, the quality accounting of wherein said PLA is 25-39.5%, described numb base fiber is by one or more mixtures that form of flaxen fiber and bamboo fibre, wood-fibred, three kinds of fibers of monkey grass, and wherein the quality accounting of flaxen fiber is 51%-99%; Described flaxen fiber is one or more the mixture in tossa, ramee, sisal fiber, flax fiber.

2. PLA composite board as claimed in claim 1, is characterized in that, numb base fiber is comprised of tossa, ramee, bamboo fibre, and its quality accounting is respectively: 80%, 15%, 5%; The quality accounting of PLA and numb base fiber is respectively 39%, 61%.

3. PLA composite board as claimed in claim 1, is characterized in that, the formation of numb base fiber is tossa 60%, monkey grass 40%, and the quality accounting of PLA and numb base fiber is respectively 34%, 66%.

4. PLA composite board as claimed in claim 2, is characterized in that, numb base fiber is comprised of tossa, ramee, bamboo dimension, and its quality accounting is respectively: 60%, 20%, 20%.

5. a preparation method for PLA composite board as claimed in claim 1 or 2 or 3 or 4, is characterized in that, specifically comprises the steps:

A: one or more of flaxen fiber and bamboo fibre, wood-fibred, three kinds of fibers of monkey grass are mixed to form to numb base fiber;

B: PLA is spun into polylactic acid short-fiber;

C: polylactic acid short-fiber is mixed with numb base fiber and make composite fibrofelt;

D: to composite fibrofelt surface spraying treatment fluid;

E: finally heat composite fibrofelt and suppress and can make sheet material by the mode that roll-in or plate are pressed.

6. the preparation method of PLA composite board as claimed in claim 5, is characterized in that, described treatment fluid is one or more the mixture in fire retardant, antiseptic, antioxidant, so that fiberboard reaches antibiotic, fire-retardant serviceability.

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