Polyimides 6: Synthesis, characterization, and comparison of properties of novel fluorinated poly(ether imides)

Abstract

Five new poly(ether imides) have been prepared on reaction with oxydiphthalic anhydride (ODA) with five different diamines: 1,4‐bis(p‐aminophenoxy‐2′‐trifluoromethyl benzyl) benzene, 4,4′‐bis(p‐aminophenoxy‐2′‐trifluoromethyl benzyl) benzene, 1,3‐bis(p‐aminophenoxy‐2′‐trifluoromethyl benzyl) benzene, 2,6‐bis(p‐aminophenoxy‐2′‐trifluoromethyl benzyl) pyridine, and 2,5‐bis(p‐aminophenoxy‐2′‐trifluoromethyl benzyl) thiophene. Synthesized polymers showed good solubility in different organic solvents. The polyimide films have low water absorption of 0.3–0.7%, low dielectric constants of 2.82–3.19 at 1 MHz, and high optical transparency at 500 nm (>73%). These polyimides showed very high thermal stability with decomposition temperatures (5% weight loss) up to 531°C in air and good isothermal stability; only 0.4% weight loss occurred at 315°C after 5 h. Transparent thin films of these polyimides exhibited tensile strength up to 147 MPa, a modulus of elasticity up to 2.51 GPa and elongation at break up to 30% depending upon the repeating unit structure. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 821–832, 2004

Thermal, mechanical, and dielectric properties of novel fluorinated copoly(imide siloxane)s

“…The glass transition values of the synthesized poly(imide siloxane)s are summarized in Table IV. In comparisons to the poly(imidesiloxane)s synthesized from ODPA, 44,49 these polymers showed a marked decrease in the T g values probably due to two ether linkages present in the BPADA hence greater flexibility leading to lower glass transition temperatures. Compared to the homo poly(etherimide)s synthesized from BPADA, 48 these poly(imide siloxane)s showed lower glass transition temperature and as expected the glass transition temperatures decreased as the siloxane loading is increased.…”

Polyimides 7: Synthesis, characterization, and properties of novel soluble semifluorinated poly(ether imide)s

“…It was attempted to obtain 10% (W/V) solution of all polymers in many organic solvents. In general the poly(ether imide)s showed very good solubility in many organic solvents and better than the analogous polymers derived previously from the diamine monomers I-V. [24][25][26][27][28] The polymers, which are derived from 6FDA…”

Fluorosilicones and Other Fluoropolymers

“…For the polymerization reaction, a one-pot solution imidization technique was carried out at a reaction temperature of 180 °C in orthodichlorobenzene solvent. This indicates high thermal stability of the poly(imide siloxane)s although the value was slightly lower than that of the analogous homopolymers without siloxane moiety [72]. The enhanced solubility of the prepared polymers was attributed to the simultaneous effect of the -CF 3 groups, which increased the FFV by disrupting chain packing, and the siloxane moiety incorporated into the polyimide backbone, which greatly enhanced chain flexibility, and which contributed to the ease of penetration of the solvent between the polymer chains.…”

“…Scheme 6.16 shows the structure of fluorinated random copoly(imide siloxane) with ODPA as the dianhydride unit. [72]. The synthesized polymers had excellent solubility in many different organic solvents such as chloroform (CHCl 3 ), dichloromethane (CH 2 Cl 2 ), dimethylformamide (DMF), N,N-dimethyl acetamide (DMAc), and N-methyl-2-pyrrolidinone (NMP) compared with previously reported homopolyimides [72] without siloxane moiety.…”