聚酰亚胺薄膜（Polyimide Film）是世界上性能好的薄膜类绝缘材料，由均苯四甲酸二酐（PMDA）和二胺基二苯醚（DDE）在强极性溶剂中经缩聚并流延成膜再经亚胺化而成。聚酰亚胺薄膜具有优良的耐高低温性、电气绝缘性、粘结性、耐辐射性、耐介质性，能在－269℃～280℃的温度范围内长期使用，短时可达到400℃的高温。

　　      被称为“黄金薄膜”的聚酰亚胺薄膜具有卓越的性能，它广泛的应用于空间技术、F、H级电机、电器的绝缘、FPC（柔性印刷线路板）、TAB（压敏胶带基材）、航天、航空、计算机、电磁线、变压器、音响、手机、电脑、冶炼、采矿电子元器件工业、汽车、交通运输、原子能工业等电子电器行业。

 

 

Polyimide film

Upilex^®-S

 

Property	Unit	Characteristic value						Test method
		Upilex®-25S				Upilex®-75S
		-269°C	-196°C	25°C	300°C	25°C	200°C
Tensile strength	MPa	735	647	520	290	360	270	ASTM D882
Stress at 5% elongation	MPa	-	-	260	90	210	110	ASTM D882
Elongation	%	10	15	42	67	50	80	ASTM D882
Tensile modulus	MPa	-	-	9,100	3,700	6,900	3,800	ASTM D882
Tear strength-initiation [Graves]	N	-	-	230	-	290	-	ASTM D1004
Tear strength-propagation [Elmendorf]	N	-	-	3.2	-	4.2	-	ASTM D1922
Folding endurance [MIT]	Cycles	-	-	>100,000	-	>25,000	-	ASTM D2176
Density	×103kg/ m3	-	-	1.47	-	1.47	-	ASTM D1505
Coefficient of kinetic friction (film-to-film)	-	-	-	0.4	-	0.4	-	ASTM D1894

2. Electrical Properties

Upilex^®-S exhibits excellent electrical characteristics over a wide range of temperatures and frequencies. Even at high temperatures, Upilex^®-S shows almost no deterioration in its electrical properties, unlike other plastic-type films. It also displays a low level of electrical insulation defects, making it an optimal choice for electrical and electronic uses that demand high reliability.

Property	Unit	Characteristic value				Test conditions	Test method
		Upilex®-25S		Upilex®-75S
		25°C	200°C	25°C	200°C
Dielectric strength	kV	6.8	6.8	11	11	50Hz	ASTM D149
Dielectric constant	-	3.5	3.3	3.3	3.2	1kHz	ASTM D150
Dissipation factor	-	0.0013	0.0078	0.0038	0.0056	1kHz	ASTM D150
Volume resistivity	Ωm	1015	1013	1014	1014	DC 100V	ASTM D257
Surface resistivity	Ω	>1017	1015	>1016	1015	DC 100V	ASTM D257

3. Thermal Properties

Upilex^®-S boasts the highest heat resistance of any plastic film currently available. Its major features include a high starting temperature for thermal decomposition, smaller values of both heat shrinkage and thermal linear expansion coefficients, as well as flame resistance (UL94 VTM-0). Therefore, Upilex^®-S varies little in size even when heated. This makes it ideal for use in FPC and TAB-tape substrates composed of minute circuits.

Property	Unit	Characteristic value			Test condition (test method)
		Upilex®-25S	Upilex®-75S
Heat shrinkage	%	0.1	0.01		200°C, 2 hours, ASTM D1204
Thermal linear expansion coefficient (50-200°C)	ppm/K	12	20		Values determined by minute linear expansion tester at 5°C/min. temperature increments
Melting point	°C	None
Specific heat	kJ/(kg·K)	1.13			Differential scanning calorimeter
Temperature index	°C	290			Heat treatment: 20,000 hours
Non-flammability	-	UL94VTM-0 (Exceeding 7.5 μm)			UL94 File No. 48133
Oxygen index	%	66			JIS K7201
Thermal conductivity	W/(m·K)	0.290			Laser flash method

4. Chemical-Resistant Properties

Upilex^®-S is insoluble in all organic solvents and is sufficiently resistant to virtually any chemical, including inorganic acid and alkali solution. This chemical resistance provides exceptional physical properties as well as superior dimensional stability when Upilex^®-S exposed to chemicals.

Property		Characteristic value (Upilex-®-S)			Test condition	Test method
		Strength retained (%)	Elongation retained (%)	Modulus retained (%)
Resistance to:						ASTM D882
10% sodium hydroxide		80	60	95	Immersion at 25°C for 5 days
Glacial acetic acid		100	95	100	Immersion at 110°C for 5 weeks
Water	PH=1.0	95	85	100	Immersion at 100°C for 2 weeks
	PH=4.2	95	85	100	Immersion at 100°C for 2 weeks
	PH=8.9	95	85	100	Immersion at 100°C for 2 weeks
	PH=10.0	95	85	100	Immersion at 100°C for 4 days
Water absorption		1.4%			Immersion in water at 23°C for 24 hours	ASTM D570
		0.8%			Immersion in water at 23°C for 24 hours
Gas permeability
Water vapor		1.7×10-3kg/m2/25μm			38°C, 90% RH for 24 hours	ASTM E96
Oxygen		0.8×10-6m3/m2/25μm			30°C, 1 atm for 24 hours	ASTM D1434
Carbon dioxide		1.2×10-3m3/m2/25μm			30°C, 1 atm for 24 hours	ASTM D1434

5. Environmental Resistance

Upilex^®-S features low water absorption and hygroscopic expansion. Another advantage inherent in Upilex^®-S is its low absorption/desorption speeds. All these combine to delivery high dimensional stability even when moisture is absorbed. It also delivers exceptional weather resistance as shown in the figures below.

General Properties of Various Heat-Resistant Films

Property	Unit	Upilex®-S	Conventional polyimide	Polyester	Polysulfone	Polytetra fluoroethylene
Density	g/cm3	1.47	1.42	1.38-1.41	1.24-1.25	2.1-2.2
Tensile strength	MPa	520	173	137-245	58-74	11-31
Elongation	%	42	70	60-170	60-110	100-400
Tensile modulus	MPa	9,120	2,961	-	-	-
Tear strength-initiation (Graves)	N	226	197	177-530	39	-
Tear strength-propagation	N	3.24	3.14	4.90-10.79	3.92-4.90	3.92
Resistance to organic solvents	-	Excellent	Excellent	Excellent	Excellent	Excellent
Resistance to strong acids	-	Good	Good	Good	Excellent	Excellent
Resistance to strong alkalis	-	Good	Poor	Good	Excellent	Excellent
Dielectric constant	-	3.5	3.5	3.2	3.1	2.1
Dissipation factor	-	0.0013	0.003	0.005	0.0008	0.0002

(Modern Plastics Encyclopedia)

Upilex^® Grades and Area Factors

Property	Grade	Thickness (μm)	Width (mm)	Area factor (m2/kg)
Upilex®-S
	12.5SN	12.5	508/1,016	54.4
	25S	25	508/1,016	27.2
	50S	50	508/1,016	13.6
	75S	75	508/1,016	9.1
	125S	125	508/1,016	5.4