Polymer aerogel with improved mechanical and thermal properties

An aerogel comprising an open-cell structured polymer matrix that includes 5 wt. % to 50 wt. % of a polyamic amide polymer, based on the total weight of the aerogel,

• wherein the aerogel comprises pores and at least 90% of the pore volume of the aerogel is made up of pores with an average pore diameter of 100 nanometers (nm) to less than 500 nm;
• wherein the aerogel has a porosity of at least 80%, as measure according to ASTM D4404-10,
• wherein the aerogel has a density of 0.05 g/cm3 to 0.5 g/cm3,
• wherein the aerogel is thermally stable to resist browning at 330° C.;
• and
• wherein the polyamic amid polymer has a repeating structural unit of
• where each Z has the following structure:
• where R3, R4, and R5 are each individually a hydrogen (H) atom, an alkyl group, or a substituted alkyl group, with the proviso that at least one of R3, R4, and R5 is an alkyl group, or a substituted alkyl group,
• X is a first organic group derived from the at least one diamine selected from 4,4′-oxydianiline, 3,4′-oxydianiline, 3,3-oxydianiline, p-phenylenediamine, m-phenylenediamine, o-phenylenediamine, diaminobenzanilide, 3,5-diaminobenzoic acid, 3,3′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfones, 1,3-bis-(4-aminophenoxy)benzene, 1,3-bis-(3-aminophenoxy)benzene, 1,4-bis-(4-aminophenoxy)benzene, 1,4-bis-(3-aminophenoxy)benzene, 2,2-Bis [4-(4-aminophenoxy)phenyl]-hexafluoropropane, 2,2-bis(3-aminophenyl)-1,1,1,3,3,3-hexafluoropropane, 4,4′-isopropylidenedianiline, 1-(4-aminophenoxy)-3-(3-aminophenoxy)benzene, 1-(4-aminophenoxy)-4-(3-aminophenoxy)benzene, bis-[4-(4-aminophenoxy)phenyl]sulfones, 2,2-bis [4-(3-aminophenoxy)phenyl]sulfones, bis-[4-(4-aminophenoxy]phenyl) ether, 2,2′-bis-(4-aminophenyl)-hexafluoropropane, (6F-diamine), 2,2′-bis-(4-phenoxyaniline) isopropylidene, meta-phenylenediamine, para-phenylenediamine, 1,2-diaminobenzene, 4,4′-diaminodiphenylmethane, 2,2-bis(4-aminophenyl)propane, 4,4′-diaminodiphenylsulfide, 4,4′ diaminodiphenylpropane, 4,4′-diaminodiphenylsulfone, 3,4′ diaminodiphenylether, 4,4′-diaminodiphenylether, 2,6-diaminopyridine, bis(3-aminophenyl) diethyl silane, 4,4′-diaminodiphenyl diethyl silane, benzidine, dichlorobenzidine, 3,3′-dimethoxybenzidine, 4,4′-diaminobenzophenone, N,N-bis(4-aminophenyl)-n-butylamine, N,N-bis(4-aminophenyl)methylamine, 1,5-diaminonaphthalene, 3,3′-dimethyl-4,4′-diaminobiphenyl, 4-aminophenyl-3-aminobenzoate, N,N-bis(4-aminophenyl)aniline, bis(p-beta-amino-t-butylphenyl) ether, p-bis-2-(2-methyl-4-aminopentyl)benzene, p-bis(1,1-dimethyl-5-aminopentyl)benzene, 1,3-bis(4-aminophenoxy)benzene, m-xylenediamine, p-xylenediamine, 4,4′-diaminodiphenyletherphosphine oxide, 4,4′-diaminodiphenyl N-methylamine, 4,4′-diaminodiphenyl N-phenylamine, amino-terminal polydimethylsiloxanes, amino-terminal polypropyleneoxides, amino-terminal polybutyleneoxides, 4,4′-methylenebis(2-methylcyclohexylamine), 1,2-diaminoethane, 1,3-1,5-diaminopentane, 1,6-diaminopropane, 1,4-diaminobutane, diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 4,4′-methylenebisbenzeneamine, 2,2′-dimethylbenzidine, (also known as 4,4′-diamino-2,2′-dimethylbiphenyl (DMB), bisaniline-p-xylidene, 4,4′-bis(4-aminophenoxy) biphenyl, 3,3′-bis(4 aminophenoxy) biphenyl, 4,4′-(1,4-phenylenediisopropylidene)bisaniline, or 4,4′-(1,3-phenylenediisopropylidene)bisaniline, and
• and Y is a second organic group derived from the at least one dianhydride selected from hydroquinone dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, pyromellitic dianhydride, 3,3′,4,4′-benzophenone-tetracarboxylic dianhydride, 4,4′-oxydiphthalic anhydride, 3,3′,4,4′-diphenylsulfone-tetracarboxylic dianhydride, 4,4′-(4,4′-isopropylidenediphenoxy)bis(phthalic anhydride), 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 4,4′-(hexafluoroisopropylidene)diphthalic anhydride, bis(3,4-dicarboxyphenyl)sulfoxide dianhydride, polysiloxane-containing dianhydride, 2,2′,3,3′-biphenyltetracarboxylic dianhydride, 2,3,2′,3′-benzophenonetetracarboxylic dianhydride, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride, naphthalene-2,3,6,7-tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, 4,4′-oxydiphthalic dianhydride, 3,3′,4,4′-biphenylsulfone tetracarboxylic dianhydride, 3,4,9,10-perylene tetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)sulfide dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropene, 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,7-dichloronapthalene-1,4,5,8-tetracarboxylic dianhydride, 2,3,6,7-tetrachloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, phenanthrene-8,9,10-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride;
• benzene-1,2,3,4-tetracarboxylic dianhydride, or thiophene-2,3,4,5-tetracarboxylic dianhydride.