JP2004250509A - Nylon-11 / polyfluorovinylidene blend film and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-axially crystal-oriented material which comprises a nylon-11 / polyfluorovinylidene (PVdF) blend, is obtained by crystallizing the PVdF in an oriented matrix of the nylon-11, and has improved dynamic characteristics by controlling the orientation of the PVdF, and to provide a method for producing the same. <P>SOLUTION: This multi-axially crystal-oriented material comprises a blend film comprising the nylon-11 and the polyfluorovinylidene (PVdF), wherein the crystal axis (c axis) of the nylon-11 in the molecular chain direction and the crystal axis (a axis) of the polyfluorovinylidene in the direction vertical to the molecular chain direction are together oriented in the stretching direction. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a polyaxially oriented material comprising a nylon-11 / polyvinylidene fluoride blend and a method for producing the same.
[0002]
[Prior art]
Conventionally, a molded article comprising polyvinylidene fluoride and nylon 12 and fibrillated with a molded article exhibiting an anisotropic molten form (liquid crystal) and having excellent chemical resistance, abrasion resistance and mechanical properties has been disclosed. I have. (See Patent Document 1)
Further, it is known from the shift of the band of the infrared absorption spectrum and the composition dependence of the glass transition that there is a specific interaction between the amide group of nylon and the CF bond of PVdF. (See Non-Patent Document 1)
[Patent Document 1] Japanese Patent No. 2614649 [Non-Patent Document 1] Gao, J .; I. Scheibeim, Macromolecules, 33, 7564 (2000) "Dipolar Intermolecular Interactions, Structural Development, and Electronic Components of Ferroelectric Properties.
[0003]
[Problems to be solved by the invention]
The present invention provides a nylon-11 / polyvinylidene fluoride blend having excellent physical properties such as piezoelectricity, chemical resistance, abrasion resistance, heat resistance, strength and elastic modulus, but further improvement in mechanical properties. is necessary. By crystallizing PVdF in an orientation matrix of nylon-11, by controlling the orientation of PVdF, a polyaxial crystal orientation material comprising a nylon-11 / polyvinylidene fluoride blend was prepared, and nylon-11 / polyfluoride was produced. Improve the mechanical properties of vinylidene blend.
[0004]
[Means for Solving the Problems]
In the blend film composed of nylon-11 and polyvinylidene fluoride (PVdF), the crystal axis (c-axis) in the molecular chain direction of nylon-11 and the crystal axis (a-axis) in the direction perpendicular to the molecular chain of polyvinylidene fluoride are both stretched. A multi-axial crystal oriented material is prepared.
Specifically, nylon-11 / PVdF is kneaded with a kneading extruder, then formed into a sheet by hot pressing, and uniaxially stretched. Thereafter, the PVdF is melted at a temperature lower than the melting point of nylon-11 and higher than the melting point of PVdF, and the PVdF is crystallized at 80 to 135 ° C.
[0005]
BEST MODE FOR CARRYING OUT THE INVENTION
The blend of nylon-11 (polyundecaneamide) and polyvinylidene fluoride (PVdF) used in the present invention may have any blending ratio. 80: 70-20 (mass ratio), more preferably nylon-11 (polyundecaneamide): polyvinylidene fluoride = 40-70: 60-30 (mass ratio).
For example, as a typical example, nylon-11 and PVdF powder are mixed (mixing mass ratio: nylon-11 / PVdF = 4/6 to 7/3), introduced into a kneading extruder, and melted. Knead and extrude. The temperatures of the inlet, cylinder and die are 150-180 ° C, 160-190 ° C and 195-225 ° C, respectively (preferably 160-170 ° C, 170-180 ° C and 205-215 ° C, respectively). Then, it is melted at 215 ° C. by a hot press to form a sheet. Further, the film is uniaxially stretched twice or more (preferably three times or more) at 20 to 180 ° C, preferably 120 to 150 ° C. Then, after constraining the form and melting the PVdF at a temperature lower than the melting point of nylon-11 and higher than the melting point of PVdF (preferably 165 to 175 ° C), 80 to 135 ° C (preferably 110 to 125 ° C) Crystallize PVdF in)).
[0006]
【Example】
The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
(Example 1)
Nylon-11 and PVdF powder are mixed (mixing ratio: nylon-11 / PVdF = 5/5), introduced into a kneading extruder, kneaded and extruded in a molten state. The temperatures of the inlet, cylinder, and die are 165 ° C, 185 ° C, and 210 ° C, respectively. Then, it is melted at 215 ° C. by a hot press and formed into a sheet. Further, at 145 ° C., the film is uniaxially stretched four times. After constraining the morphology, the PVdF was melted at 170 ° C. for 5 minutes and then crystallized at 120 ° C.
When observed with a confocal laser scanning microscope after staining with fluorescein, it is observed that PVdF domains having a diameter of 2 to 10 μm and a length of 10 to 50 μm are arranged in an oriented matrix of nylon. According to wide-angle X-ray diffraction, for nylon, the crystal axis in the molecular chain direction (crystal c-axis) is oriented in the stretching direction, whereas for PVdF, the crystal a-axis, which is the crystal axis perpendicular to the molecular chain, is oriented. Are oriented in the stretching direction, and it can be confirmed that a multiaxial crystal orientation structure is formed. (FIG. 2d)
According to the tensile test and the dynamic viscoelasticity measurement, the breaking strength was 140 MPa, the breaking elongation was 32.5%, and the dynamic storage modulus was 2.1 GPa. (Fig. 3)
(Example 2)
A blend sheet was prepared in the same manner as in Example 1, and uniaxially stretched four times at 145 ° C. After constraining the morphology, the PVdF was melted at 170 ° C. for 5 minutes and then crystallized at 85 ° C. According to wide-angle X-ray diffraction, for nylon, the crystal axis in the molecular chain direction (crystal c-axis) is oriented in the stretching direction, whereas for PVdF, the crystal a-axis, which is the crystal axis perpendicular to the molecular chain, is oriented. Are oriented in the stretching direction, and it can be confirmed that a multiaxial crystal orientation structure is formed. (FIG. 2c)
[0007]
(Comparative example)
(Comparative Example 1)
A blend sheet was prepared in the same manner as in the example, and uniaxially stretched four times at 145 ° C. Melting and crystallization of PVdF were not performed.
Observation with a confocal laser scanning microscope shows that domains of PVdF having a diameter of 2 to 10 μm and a length of 10 to 50 μm are arranged in an alignment matrix of nylon. According to wide-angle X-ray diffraction, the crystal axis in the molecular chain direction (crystal c-axis for both nylon and PVdF) is oriented in the stretching direction for both nylon and PVdF. (FIG. 1a)
According to the tensile test and the dynamic viscoelasticity measurement, the breaking strength was 164 MPa, the breaking elongation was 17%, and the dynamic storage modulus was 2.1 GPa. (Fig. 3)
(Comparative Example 2)
A blend sheet was prepared in the same manner as in the example, and uniaxially stretched four times at 145 ° C. After melting the PVdF at 170 ° C. for 5 minutes, the PVdF was crystallized at 0 ° C. in ice water.
Observation with a confocal laser scanning microscope shows that domains of PVdF having a diameter of 2 to 10 μm and a length of 10 to 50 μm are arranged in an alignment matrix of nylon. According to wide-angle X-ray diffraction, the crystal axis in the molecular chain direction (the crystal c-axis for both nylon and PVdF) is oriented in the stretching direction for both nylon and PVdF. (FIG. 2a)
According to the tensile test and the dynamic viscoelasticity measurement, the breaking strength was 138 MPa, the breaking elongation was 23%, and the dynamic storage modulus was 2.2 GPa.
[0008]
(Comparative Example 3)
The mechanical properties of the unstretched film (non-oriented film) of the blend sheet (nylon-11 / PVdF = 5/5) were evaluated. The breaking strength was 24 MPa, the breaking elongation was 4.2%, and the dynamic storage modulus was 1.2 GPa.
(Comparative Example 4)
A blend sheet was prepared in the same manner as in the example, and uniaxially stretched four times at 145 ° C. After melting the PVdF at 170 ° C. for 5 minutes, the PVdF was crystallized at 0 ° C. in ice water without restricting the morphology. The orientation of PVdF was disturbed, and an unoriented crystal structure was formed. (FIG. 1b)
[0009]
【The invention's effect】
By controlling the orientation of PVdF by crystallizing PVdF in an orientation matrix of nylon-11, while maintaining the excellent physical properties (chemical resistance, abrasion resistance, piezoelectricity) of PVdF, The mechanical properties could be improved. Applicable to a wide range of uses as various structural materials such as high-strength plastic films.
[Brief description of the drawings]
FIG. 1 is a wide-angle X-ray diffraction image of nylon-11 / PVdF (a) a stretched sample (b) a sample heat-treated at 170 ° C. for 5 minutes without restricting the form after stretching.
FIG. 2 shows a crystallization temperature dependence diagram of a wide-angle X-ray diffraction image of nylon-11 / PVdF crystallized at each temperature after melting PVdF at 170 ° C. for 5 minutes after stretching (a) 0 ° C .; (b) 75 (C) 85 ° C; (d) 120 ° C
FIG. 3 is a stress-strain curve of a stretched sample of nylon-11 / PVdF (a) parallel direction (b) vertical direction

Claims (3)

It is a blend film composed of nylon-11 and polyvinylidene fluoride (PVdF), and the crystal axis (c-axis) in the molecular chain direction of nylon-11 and the crystal axis (a-axis) perpendicular to the molecular chain of polyvinylidene fluoride are both present. A polyaxial crystal orientation material oriented in the stretching direction. Nylon-11: The multiaxial crystal orientation material according to claim 1, which is a blend film composed of polyvinylidene fluoride (PVdF) = 40 to 70:60 to 30 (mass ratio). Nylon-11 / PVdF is kneaded with a kneading extruder, then formed into a sheet by hot pressing, and then uniaxially stretched. A method for producing a multiaxially oriented material, characterized in that the temperature is kept at 80 to 135 ° C. to crystallize PVdF.

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