Transcript Injection Molding Machine Controller

Influences of Sequential Biaxial
Stretching Parameters on the
Interior Structure of
Polypropylene Membrane
Liang-Yu Chen, Chung-Cheng Su and Ren-Haw Chen
Department of Mechanical Engineering
National Chiao Tung University
2
Application of polymer
membrane
•
Packaging
•
Water filter
•
Battery ion exchange
membranes
Barrier
Filter
3
Membrane Sequential
Biaxial Stretching
Extruder
Cooling
Roller
Transverse Direction
(TD) Stretching
Cutting
Machine Direction
(MD) Stretching
Melt extrusion die
Drawing
Lamellar
Interlamellar
region
Bridging
structure
Micropores
Stretching
Direction of
uniaxial stretching
1μm
4
Advantage of
polypropylene(PP)
•
Resistant to many chemical solvents
•
Fine mechanical strength
•
Low glass transition temperature
•
Semi-crystalline
5
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Materials
•
Polypropylene ( Sumitomo
Chemical Asia, AV161)
Properties
Method
Unit
Value
Density
ASTM
D792
g/cm3
0.9
•
Mold temperature 130°C
Tensile
Strength
ASTM
D638
MPa
24
•
70 x 70 x 0.5 mm
Rockwell
Hardness
ASTM
D785
HRC
88
Melt
temperature
ISO
3146
°C
170
Heat
Deflection
Temperature
ASTM
D648
°C
114
Melt Flow
Rate
ASTM
D1238
g/10min
5
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Stretching device
Servo Motor
Controller
Servo Motor
Roller
With Controllable:
Heater
Plate
• Temperature
Temperature
Controller
Grippers
• Stretching Speed
• Drawing Ratio
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Stretching procedure
PP Sheets
Injection
Molding
M
D
Stretching
TD Pre stretching
T
D
Stretching
Membrane
Analysis
Plastification
Heating
Heating
Heating
Dimensional
Measurement
Injection
MD
Stretching
TD
Prestretching
TD
Stretching
Optical
Microscopic
Observation
Cooling
Ejection
Thermal
Setting
Cooling
Thermal
Setting
Cooling
Thermal
Setting
Cooling
Polarized
Optical
Microscopic
Observation
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Optical microscopic
observation
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Effects of mold temperature on
interior structure of membrane
Polarized optical microscopy micrograph cross-section of PP
sheets formed at various mold temperatures. (a)90°C, (b)120°C,
(c)130°C.
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Interior structures of the
membrane formed by stretching
The interior structure of membrane.
(a)after MD stretching, (b)after TD
stretching.
The micrographs of structure of PP sheet
before stretching.
The net-like interior structure of
membrane
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Effects of MD stretching
temperature on membrane’s
interior structures
(b)
(a)
110°C
(c)
120°C
(b)
(a)
(d)
130°C
(c)
(e)
140°C
(e)
(d)
MD
Drawing
Ratio
TD Prestretching
Temperature
Ratios of TD Prestretching to Total
TD Stretching
TD Stretching
Temperature
TD
Drawing
Ratio
↓
300%
90°C
60%
120°C
200%
MD
MD Stretching
Temperature
(a)110°C, (b)120°C, (c)130°C, (d)140°C, (e)150°C
150°C
TD
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mean size of the net-like
Structures (µm^2)
MD stretching temperature
MD stretching temperature
thickness of the
membrane (µm)
percentage of the net-like
structure
MD stretching temperature
standard deviation of sizes
of the net-like structures
(µm^2)
Effects of MD stretching
temperature on membrane’s
interior structures
MD stretching temperature
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Effects of MD drawing ratio on
membrane’s interior structures
(a)
(b)
260%
(a)
(c)
280%
(b)
(e)
(d)
300%
320%
(e)
(d)
(c)
MD
Drawing
Ratio
TD Prestretching
Temperature
Ratios of TD Prestretching to Total
TD Stretching
TD Stretching
Temperature
TD
Drawing
Ratio
120°C
↓
90°C
60%
120°C
200%
MD
MD Stretching
Temperature
(a)260%, (b)280%, (c)300%, (d)320%, (e)340%
340%
TD
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thickness of the
membrane (µm)
standard deviation of sizes
of the net-like structures
(µm^2)
percentage of the net-like
structure
MD drawing ratio
MD drawing ratio
mean size of the net-like
Structures (µm^2)
Effects of MD drawing ratio on
membrane’s interior structures
MD drawing ratio
MD drawing ratio
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Effects of TD pre-stretching
temperature on membrane’s
interior structures
(a)
(b)
80°C
(a)
(c)
90°C
(b)
(e)
(d)
100°C
110°C
(e)
(d)
(c)
MD
Drawing
Ratio
TD Prestretching
Temperature
Ratios of TD Prestretching to Total
TD Stretching
TD Stretching
Temperature
TD
Drawing
Ratio
120°C
300%
↓
60%
120°C
200%
MD
MD Stretching
Temperature
(a)80°C, (b)90°C, (c)100°C, (d)110°C, (e)120°C
120°C
TD
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TD pre-stretching temperature
mean size of the net-like
Structures (µm^2)
TD pre-stretching temperature
thickness of the
membrane (µm)
TD pre-stretching temperature
standard deviation of sizes
of the net-like structures
(µm^2)
percentage of the net-like
structure
Effects of TD pre-stretching
temperature on membrane’s
interior structures
TD pre-stretching temperature
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Effects of ratio of TD pre-stretching to
total TD stretching on membrane’s
interior structures
(a)
(b)
20%
(a)
(c)
40%
(b)
(e)
(d)
60%
80%
(e)
(d)
(c)
MD
Drawing
Ratio
TD Prestretching
Temperature
Ratios of TD Prestretching to Total
TD Stretching
TD Stretching
Temperature
TD
Drawing
Ratio
120°C
300%
90°C
↓
120°C
200%
MD
MD Stretching
Temperature
(a)20%, (b)40%, (c)60%, (d)80%, (e)100%
100%
TD
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60%
110%
ratios of TD pre-stretching
to total TD stretching
mean size of the net-like
Structures (µm^2)
10%
10%
60%
110%
ratios of TD pre-stretching
to total TD stretching
thickness of the
membrane (µm)
standard deviation of sizes
of the net-like structures
(µm^2)
percentage of the net-like
structure
Effects of ratio of TD pre-stretching to
total TD stretching on membrane’s
interior structures
10%
60%
110%
ratios of TD pre-stretching
to total TD stretching
10%
60%
110%
ratios of TD pre-stretching
to total TD stretching
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Effects of TD stretching
temperature on membrane’s
interior structures
(a)
(b)
110°C
(a)
(c)
120°C
(b)
(e)
(d)
130°C
140°C
(e)
(d)
(c)
MD
Drawing
Ratio
TD Prestretching
Temperature
Ratios of TD Prestretching to Total
TD Stretching
TD Stretching
Temperature
TD
Drawing
Ratio
120°C
300%
90°C
60%
↓
200%
MD
MD Stretching
Temperature
(a)110°C, (b)120°C, (c)130°C, (d)140°C, (e)150°C
150°C
TD
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mean size of the net-like
Structures (µm^2)
TD stretching temperature
TD stretching temperature
thickness of the
membrane (µm)
percentage of the net-like
structure
TD stretching temperature
standard deviation of sizes
of the net-like structures
(µm^2)
Effects of TD stretching
temperature on membrane’s
interior structures
TD stretching temperature
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Effects of TD drawing ratio on
membrane’s interior structures
(a)
(b)
180%
(a)
(c)
200%
(b)
(e)
(d)
220%
240%
(e)
(d)
(c)
MD
Drawing
Ratio
TD Prestretching
Temperature
Ratios of TD Prestretching to Total
TD Stretching
TD Stretching
Temperature
TD
Drawing
Ratio
120°C
300%
90°C
60%
120°C
↓
MD
MD Stretching
Temperature
(a)180%, (b)200%, (c)220%, (d)240%, (e)260%
260%
TD
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mean size of the net-like
Structures (µm^2)
TD drawing ratio
thickness of the
membrane (µm)
percentage of the net-like
structure
TD drawing ratio
standard deviation of sizes
of the net-like structures
(µm^2)
Effects of TD drawing ratio on
membrane’s interior structures
TD drawing ratio
TD drawing ratio
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For sequential biaxial
stretching process
• MD
stretching
Increasing the orientation of the structure of
the membrane
• TD
pre-stretching (with low temperature)
Separating the interior structure of the
membrane
• TD
stretching
Leads to a net-like interior structure
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During MD stretching
• Increasing
MD stretching temperature
The uniformity of the structure of the
membrane would increased
Improves the generation of fibers in the netlike interior structure
• Increasing
MD drawing ratio
The uniformity of the structure of the
membrane would increased
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During TD pre-stretching
• Increasing
TD per-stretching
temperature
Significantly reduces the number of net-like
structures
• Increasing
the ratio of TD pre-stretching
to total TD stretching
Increases the number of net-like structures
and improves the consistency of their sizes
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During TD stretching
• Increasing
the stretching temperature
Reduces the amount of net-like structures
formed
• Increasing
TD drawing ratio
Increases the size of the formed net-like
structures
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