METHOD OF MANUFACTURING BIODEGRADABLE POLYMER THIN FILM USING COEXTRUSION PROCESS

The present invention refers to various modification may have various can apply in the embodiment which is, in the embodiment example are specific detailed drawing and the broadcast receiver.

However, the present invention is defined with respect to a particular embodiment form which are not included, all changing range of idea and techniques of the present invention, including the water to replacement should understood to evenly.

In hereinafter, the present invention according to in the embodiment with reference to the attached drawing are detailed as follows.

Figure 1 shows a device of the present invention in one preferred biodegradable polymer for a high pressure liquid coolant also in the embodiment according to number and shown in the drawing, Figure 2 shows a device indicating the number through the tank 3 layer film structure of Figure 1 are disclosed.

According to the in the embodiment, biodegradable polymer in order to enhance processability coextruded method for plural times.

Generally coextrusion method includes a plurality of extruder effected. Pressure each in an extruder screw rotation of different molten polymer are determined block see you in a laminar flow is formed, simultaneously a blower fan. The film is extruded through an extrusion method in multilayer ceramic mounting through a data structure used for a determined number of and designing. For closely contacting to the discharged molten polymer thin air has cooled while rolling my wound on penetration. The, molten polymer is wrapped around the tension roll is set larger than the objective speed of this film stretching process has age and stretch where it is molten polymer.

At a stretch and non-extrusion process tracks for aspect ratio plays an important process conditions (draw ratio) is less than the extrusion rate contrast rotating speeds of the big. In addition aspect ratio (aspect ratio) is molten polymer is extruded from the slit width of the slit and roll distance big contrast. In one embodiment of the drawing process determining final thickness and width such tracks stretched film aspect ratio could be bonded each other.

In particular stretch ratio due to high-speed production but not greater thinner film whose width is viscoelastic polymer generator system and a neck (neck provided in) developing it has - in age. In addition greater film thickness of neck - in the outputs of the filters include a plurality system and a thicker than the thickness among sites for instance - it has edge bead (edge-a beads) developing age. Generally two exposed polymer processability can be polymer with excellent suitability determining a developing one's increase.

In the embodiment of the present invention according to one, biodegradable polymer processability through coextrusion method on the base.

The reference also 1, which can be biodegradable polymer extruder is number 1, number 2 (petrochemical based polymer) general polymer extruder is charged substrate.

Number 1 in the extruder the molten biodegradable polymer block is disposed points of amount, cooled by a cooling roll are mounted number 1 extruder and number 2 extruder such as 2/2 while also solidified polymer outer of biodegradable polymer, polymer is encoded number tank 3 layered film disposed board body has versatility.

Preferably, the biodegradable polymer Poly (lactic acid), Poly (caprolactone), Polyhydroxybutyrate, comprising at least one poly (butylene adipate terephthalate) can.

In addition, person general conventional petrochemical based hyperbranched polymer (Low non-density polyethylene) as LDPE, LLDPE (Linear Low high-density polyethylene), HDPE (High high-density polyethylene), PVC (polyvinyl chloride) can PP (polypropylene) and comprising at least one.

Even when using existing drawing process as well as device 1 also such as edge - bead phenomenon occurs. However coextrusion method number 3 layer film structure when compared to existing tank through the wider film stretching process in that number can be high pressure liquid coolant. The edge portion of the oven is provided to both a stand-alone number - bead phenomenon even wider film number can be high pressure liquid coolant.

2 Extruder 1 through 3 layer film such as of biodegradable polymer which also stretched in a stretching are not uniform in thickness with a portion of the biodegradable polymer thin film is peeled from the general number across the wetting ability in addition polymer substrate. The supports are combined each other.

Preferably, the wetting ability of the overall length of a portion of the implementation being hereinafter 20 percent maximum number which both ends in the width direction.

I.e., a uniform thickness film which are at least about 80 percent degree total in films are disclosed.

In the embodiment according to hereinafter and in the biodegradable polymer is polylactic acid, a low density polyethylene polymer is about general described as follows.

An in-situ process whose value biodegradable polylactic acid has high solid-state etc. has been developed and the pupil. However low viscosity polymer melt strength and petrochemical (general) compared processability due to having the magnet body.

Figure 6 shows a 3 also can be used to surface tension and shear viscosity of MDI and low density polyethylene representing the result of measurement are disclosed.

With reference also to the 6 also 3, tension and shear viscosity compared to low density polyethylene polylactic acid vary low disclosed. Tension value significantly lower viscosity when molten polylactic acid having a considerably high temperature, from the molten polymer extruded air for preventing electrons from moving in relation to the form of a tension extending has lost.

In addition, optimized temperatures polylactic acid film is low draw tracks for aspect ratio under conditions of severe neck - in developing edge - bead through an other. After the phenomenon increases functional thin film having a constant thickness and wide produced a mould. However thinner thickness for high-speed production film whose width is an uneven thickness and stretch ratio of the film is set higher because of production are disclosed. On the other hand, with excellent workability such as low density polyethylene polymers are high elongation even relatively decreases the influence of neck - phosphorus - edge bead developing non exhibit substrate.

In the embodiment of the present invention according to one, polylactic acid polylactic acid - 3 - low density polyethylene porous film layer structure which can be used in physical interaction interface to a molten state turns coextruded polyethylene deformable cladding layer.

More carefully, in the lateral direction of the outer layer can be used for further contracting force drawing process two film acting as an inner layer in contact in a molten state but strongly since same by mitigating effect occurs with a low density polyethylene. The microstrip to phenomenon leads to reduced neck - in developing has been found that when edge bead - result to be coated.

Consequently, film stretching process low density polyethylene with excellent workability such as polyimid by coextrusion method using the polymer, such as polylactic acid polymer to create a relatively processability can be overcome so as to drop significantly.

In the embodiment according to the coextrusion method also 7 to 8 indicating improved processability through porous film which can be used for drawing state are disclosed.

NP is polylactic acid film, having a low density polyethylene 20 volume percent is 35 volume percent LP1 LP2, LP3 is coextruded film to 50 volume percent volume fraction of big.

Figure 7 aspect ratio (aspect ratio) is 0. 6 Condition (draw ratio) is at a non 5, 15, 25 polymer film width when represented by graph are disclosed.

The width of the film formed by which the stretch ratio generally decreases, the higher the volume fraction of low density polyethylene film it is my layer contracts less and making sure that the width of the can. In particular, even if only low density polyethylene 35 volume percent 1 applied. 5 Times width can be achieved. 35 Volume percent or more as well as the width biodegradable thin film film number than low density polyethylene can be high pressure liquid coolant.

Figure 8 NP film thickness of a film of graph while comparing LP3 are disclosed. The X axis and a shock-absorbing means away from among the semiconductor absolute value 0 means that the substrate. The value obtained by dividing an angular position of the value of the Y axis thickness of the portion of the semiconductor means other. In developing influence of neck -, film thickness to vary relative to the thickness of the both ends of the thick among number because of the stand-alone among thin film a film of uniform thickness is measured for plural times.

According to experiment results, NP film is shown to exhibit LP3 is thickened region and the second region tends to sites in the semiconductor film is relatively width direction of division of the first to fourth and viscoelasticity. I.e., low density polyethylene film inner layer coextruded multilayer film by applying a film of uniform thickness can be used for a wide compared to the film for obtaining WIPO.