Tough Polyimide Films Research Articles

Preparation and characterization of new polyimides derived from 2,2-bis[4-[2-(4-aminophenoxy)ethoxy]phenyl]sulfone

A new diamine containing sulfone and oxyethylene unit, 2,2-bis[4-[2-(4-aminophenoxy)ethoxy]phenyl]sulfone (BAEPS), was used as a monomer with various aromatic tetracarboxylic dianhydrides to synthesize polyimides via a conventional two-step procedure. The diamine was prepared through the aromatic nucleophilic substitution of bis[4-(2-hydroxyethoxy)phenyl]sulfone with p-fluoronitrobenzene in the presence of potassium carbonate, followed by catalytic reduction with hydrazine monohydrate/Pd–C. Depending on the dianhydrides used, the poly(amic acid)s obtained had inherent viscosities of 0.90–1.32 dl/g. All the poly(amic acid)s were cast from the N,N-dimethylacetamide solution and thermally converted into transparent, flexible and tough polyimide films. The polyimide films had a tensile strength range of 74–151 MPa and tensile modulus between 1.9 and 3.0 GPa. Almost all the polymers were amorphous except for that derived from dianhydride pyromellitic dianhydride (PMDA). The polyimide derived from 4,4′-hexafluoro-isopropylidenediphathalic anhydride exhibited excellent solubility in various organic solvents. These polyimides had moderate glass transition temperatures of between 185 and 222°C. The PMDA-based polyimide exhibited melting temperature at 413°C. The 10% mass loss temperatures of the polyimides were recorded in the range of 445–468 and 433–452°C in nitrogen and air atmosphere, respectively. Copyright © 1999 John Wiley & Sons, Ltd.

Synthesis and characterization of new soluble polyimides derived from 2,2-bis[3,5-dimethyl-4-(4-aminophenoxy)phenyl]propane

A diamine monomer containing isopropylidene and methyl substituted arylene ether, 2,2-bis[3,5-dimethyl-4-(4-aminophenoxy)phenyl]propane (TBAPP), was prepared in two steps. The monomer was reacted with six different aromatic tetracarboxylic dianhydrides in N.N-dimethylacetamide (DMAc) to obtain the corresponding new polyimides via the poly(amic acid) precursors and thermal or chemical imidization. The poly(amic acid)s obtained had inherent viscosities ranging from 1.38-2.10 dL . g 1 . All the poly-(amic acid)s could be cast from DMAc solutions and thermally converted into transparent, flexible, and tough polyimide films. The polyimide films had a tensile strength in the range from 52-95 MPa, an elongation at break within a range of 4-8%, and a tensile modulus in the range from 1.60-2.09 GPa. All polyimides were amorphous. The polyimides derived from diamine TBAPP had excellent solubility in various solvents except for those derived from rigid dianhydrides such as pyromellitic dianhydride and 3,3',4,4'-biphenyltetracarboxylic dianhydride. These polyimides showed glass transition temperatures between 249-293 C and decomposition temperature at 10% mass loss temperatures ranging from 460-485°C in nitrogen.

Synthesis and Properties of 1,4-Bis(4-aminophenoxy)naphthalene and Its Polyimides

A new diamine 1,4-bis(4-aminophenoxy)naphthalene (1,4-BAPON) was prepared through the nucleophilic displacement of 1,4-dihydroxynaphthalene with p-fluoronitrobenzene in the presence of K2CO3 in N,N-dimethylacetamide (DMAc), followed by catalytic reduction with hydrazine and Pd/C in ethanol. A series of novel aromatic polyimides containing 1,4-bis(aminophenoxy)naphthalene units was synthesized from 1,4-BAPON and various aromatic tetracarboxylic dianhydrides by the conventional two-stage procedure that included ring-opening polyaddition in a polar solvent such as DMAc, to give poly(amic acid)s, followed by thermal cyclodehydration to polyimides. Depending on the dianhydrides used, the poly(amic acid)s obtained had inherent viscosities of 0.81–1.33 dL g−1. All the poly(amic acid)s could be solution cast and thermally converted into transparent, flexible, and tough polyimide films. These polyimides had glass transition temperatures between 247–281°C. Thermogravimetric analyses established that these polymers were fairly stable up to 500°C, and 10% weight loss temperatures were recorded in the range of 521–581°C in nitrogen and 517–575°C in air atmosphere.

Synthesis and properties of polyimides derived from 3,3′,5,5′-tetramethyl-bis[4-(4-aminophenoxy)phenyl]sulfone

The novel diamine containing methyl-substituted arylene sulfone ether, 3,3′5,5′-tetramethylbis[4-(4-aminophenoxy)phenyl]sulfone (TBAPS), was used as a monomer with various aromatic tetracarboxylic dianhydrides to synthesize polyimides via a conventional two-stage procedure that included ring-opening polyaddition in a polar solvent such as N,N-dimethylacetamide (DMAc) to give poly(amic acid)s, followed by cyclodehydration to polyimides. The diamine was prepared through the nucleophilic displacement of bis(4-hydroxy-3,5-dimethylphenyl)sulfone with p-chloronitrobenzene in the presence of K 2 CO 3, followed by catalytic reduction. Depending on the dianhydrides used, the poly(amic acid)s obtained had inherent viscosities of 0.80−1.72 dL g −1. All the poly(amic acid)s could be cast from DMAc solutions and thermally converted into transparent, flexible and tough polyimide films. The polyimide films had a high tensile strength range 81–118 MPa, an elongation range at break 5–9% and a tensile modulus range 1.78–2.49 GPa. The polyimide derived from 4,4′-hexafluoroisopropylidenebis-phathalic anhydride had better solubility than the other polyimides. These polyimides had glass transition temperatures between 291–339 °C and 10% mass loss temperatures were recorded in the range 550–591 °C in nitrogen and 556–588 °C in air atmosphere.

Preparation and properties of polymides, polyamides and poly(amide‐imide)s based on a spirobichroman dietheramine

AbstractA novel diamine, 7,7′‐bis(4‐aminophenoxy)‐4,4,4′,4′‐tetramethyl‐2,2′‐spirobichroman (3), was synthesized and used as a monomer with various aromatic tetracarboxylic dianhydrides, dicarboxylic acids and imide ring‐containing dicarboxylic acids, to synthesize polymides, polyamides and poly(amide‐imide)s, respectively. The polyimides 5a–f were prepared from diamine 3 and various aromatic tetracarboxylic dianhydrides via a conventional two‐stage procedure. The intermediate poly(amic acid)s had inherent viscosities of 0,84 – 1,65 dL/g and could be thermally converted into transparent, flexible, and tough polyimide films. Some polyimides were readily soluble in polar solvents such as N,N‐dimethylacetamide (DMAc) and N‐methyl‐2‐pyrrolidone (NMP). The glass transition temperatures (Tg) of these polyimides were in the range of 155–280°C, and 10% weight loss temperatures were above 450°C in air or nitrogen. Furthermore, a series of polyamides and poly(amide‐imide)s having inherent viscosity between 0,40–1,69 dL/g were prepared by direct polycondensation of the diamine 3 with various aromatic dicarboxylic acids and imide ring‐containing dicarboxylic acids. All the polyamides and poly(amide‐imide)s were soluble in a variety of organic solvents and could be solution‐cast into flexible and tough films. They had Tg values in the 150–237°C range and showed no significant weight loss below 400°C in air and nitrogen atmosphere.

Synthesis and properties of polyimides, polyamides and poly(amide-imide)s from ether diamine having the spirobichroman structure

A novel spirobichroman unit containing dietheramine, 6,6′-bis(4-aminophenoxy)-4,4,4′,4′,7,7′-hexamethyl-2,2′-spirobichroman (3), was prepared by the nucleophilic substitution of 6,6′-dihydroxy-4,4,4′,4′,7,7′-hexamethyl-2,2′-spirobichroman with p-chloronitrobenzene in the presence of K2CO3 followed by hydrazine catalytic reduction of the intermediate dinitro compound. A series of polyimides were synthesized from diamine 3 and various aromatic dianhydrides by a conventional two-stage procedure through the formation of poly(amic-acid)s followed by thermal imidization. The intermediate poly(amic-acid)s had inherent viscosities of 1.00–2.78 dL/g. All the poly-(amic-acid)s could be thermally cyclodehydrated into flexible and tough polyimide films, and some polyimides were soluble in polar solvents such as N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc), and N,N-dimethylformamide (DMF). These polyimides had glass transition temperatures (Tg) in the range of 236–256°C, and 10% weight loss occurred up to 450°C. Furthermore, a series of polyamides and poly(amide-imide)s with inherent viscosities of 0.71–2.29 dL/g were prepared by direct polycondensation of the diamine 3 with various aromatic dicarboxylic acids and imide ring-containing dicarboxylic acids by means of triphenyl phosphite and pyridine. All the polyamides and poly(amide-imide)s were readily soluble in polar solvents such as DMAc, and tough and flexible films could be cast from their DMAc solutions. These polymers had glass transition temperatures in the range of 137–228°C and 10% weight loss temperatures in the range of 419–443°C in air and 404–436°C in nitrogen, respectively. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1487–1497, 1997

Synthesis and Properties of Polyimides Derived from 1,4-Bis(4-aminophenoxy)-2-tert-butylbenzene

The novel diamine containing bulky tert-butyl substituent, 1,4-bis(4-aminophenoxy)-2-tert-butylbenzene (BATB) was used as monomer with various aromatic tetracarboxylic dianhydrides to synthesize polyimides via a conventional two-stage procedure that included ring-opening polyaddition in a polar solvent such as N,N-dimethylacetamide (DMAc) to give poly(amic acid)s, followed by cyclodehydration to polyimides. BATB(II) was prepared through the nucleophilic displacement of tert-butylhydroquinone with p-chloronitrobenzene in the presence of K2CO3, followed by catalytic reduction. Depending on the dianhydride used, the poly(amic acid)s obtained had inherent viscosities of 0.76–1.79 dL g−1. All poly(amic acid)s could be cast from the DMAc solutions and thermally converted to transparent, fiexible, and tough polyimide films. The polyimide films had high tensile strength of 122–208 MPa, an elongation at breaks of 3–9%, and a tensile modulus of 1.92–2.68 GPa. Polyimides from 4,4′-sulfonyldiphthalic anhydride and 4,4′-hexafluoro-isopropylidenediphathalic anhydride had better solubility than the other polyimides. These polyimides had glass transition temperatures between 240–268°C and 10% mass loss temperatures were recorded at 479–522°C in nitrogen.

Synthesis and properties of polyimides derived from 1,6‐bis(4‐aminophenoxy)naphthalene and aromatic tetracarboxylic dianhydrides

Abstract1,6‐Bis(4‐aminophenoxy)naphthalene (I) was used as a monomer with various aromatic tetracarboxylic dianhydrides to synthesize polyimides via a conventional two‐stage procedure that included ring‐opening polyaddition in a polar solvent such as N,N‐dimethylacetamide (DMAc) to give poly(amic acid)s, followed by thermal cyclodehydration to polyimides. The diamine (I) was prepared through the nucleophilic displacement of 1,6‐dihydroxynaphthal‐ene with p‐chloronitrobenzene in the presence of K2CO3, followed by catalytic reduction. Depending on the dianhydrides used, the poly(amic acid)s obtained had inherent viscosities of 0.73–2.31 dL/g. All the poly(amic acid)s could be solution cast and thermally converted into transparent, flexible, and tough polyimide films. The polyimide films had a tensile modulus range of 1.53–1.84 GPa, a tensile strength range of 95–126 MPa, and an elongation range at break of 9–16%. The polyimide derived from 4,4′‐sulfonyldiphthalic anhydride (SDPA) had a better solubility than the other polyimides. These polyimides had glass transition temperatures between 248–286°C (DSC). Thermogravimetric analyses established that these polymers were fairly stable up to 500°C, and the 10% weight loss temperatures were recorded in the range of 549–595°C in nitrogen and 539–590°C in air atmosphere. © 1995 John Wiley & Sons, Inc.

Syntheses and properties of polyimides based on bis(p-aminophenoxy)biphenyls

Three biphenyl unit-containing diamines,4,4′-bis(p-aminophenoxy)biphenyl (IIIa), 2,2′-bis(p-aminophenoxy)biphenyl (IIIb), and 3,3′,5,5′-tetramethyl-4,4′-bis(p-aminophenoxy)biphenyl (IIIc), were prepared by the chlorodisplacement ofp-chloronitrobenzene with 4,4′-biphenol (Ia), 2,2′-biphenol (Ib), and 3,3′,5,5′-tetramethyl-4,4′-biphenol (Ic), respectively, giving the corresponding bis(nitrophenoxy) compounds IIa-c, followed by catalytic reduction with palladium (Pd) and hydrazine. Three series of polyimidesp-PI,o-PI, and Me-PI were prepared from diamines IIIa-c and aromatic tetracarboxylic dianhydrides via a two-stage procedure that included ring-opening polyaddition to give poly(amic acid)s followed by thermal cyclodehydration to polyimides. The resultant three series of poly(amic acid)s had inherent viscosities of 1.09–2.83, 0.78–1.93, and 1.55–3.09 dL/g, respectively. Almost all the poly(amic acid)s could be solution-cast and thermally converted into transparent, flexible, and tough polyimide films. All the polyimides were characterized by solubility, tensile test, wide-angle X-ray scattering measurements, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Effects of the structures of aromatic diamines and dianhydrides on the properties of polyimides were investigated.

Polyimides based on ?multiring? flexible diamines

The five benzene rings-containing (hereafter for convenience, referred to as “five-ringrd) diamines ad-bis[4-(4-aminophenoxy)phenyl]-1,4 (or 1,3)-diisopropylbenzene (p- or m-3) were prepared by a nucleophilic substitution of α,α′-bis(4-hydroxyphenyl)-1, 4 (or 1,3)-diisopropylbenzene (p- or m-1) with p-chloronitrobenzene in the presence of K2CO3 and then hydro-reduced. The polyimides were synthesized from diamine 3 and various aromatic dianhydrides via the two-stage procedure that include ring-opening polyaddition in DMAc to give poly(amic acid)s, followed by thermal conversion to polyimides. The poly(amic acid)s had inherent viscosities of 0.63–1.54 dL/g depending on the dianhydrides used. Almost all the poly(amic acid)s could be solution-cast and thermally converted into transparent, flexible, and tough polyimide films. These polyimides have glass transition temperatures in the range of 186–290°C and almost no weight loss up to 500°C in air or nitrogen atmosphere. The polyimide obtained from pyromellitic dianhydride and diamine m-3 showed two endothermic peaks of 270 and 300°C on the diagram of differential scanning calorimetry (DSC), and the other polyimides showed no endotherms on their DSC traces.