Synthesis, Characterization and Properties of New Fluorinated Poly(imide siloxane) Co-polymers from 4,4′-(Hexafluoro-isopropylidene)diphthalic Anhydride

Abstract

Several new poly(imide siloxane)s co-polymers have been prepared by the reaction of 4,4 -(hexafluoroisopropylidene)diphthalic anhydride (6FDA) with commercially available 4,4 -oxydianiline (ODA) and with five different novel trifluoromethyl-substituted diamines, each with 20 wt% aminopropyl-terminated polydimethylsiloxane (APPS). The poly(imide siloxane)s are well characterized by different spectroscopic, thermal, mechanical and electrical techniques. The synthesized polymers exhibit good solubility in different organic solvents. The 1 H-NMR indicates that the siloxane incorporation is about 17-19% for polymers 1a-f. These poly(imide siloxane) films show low water absorption rate (0.88-0.09%) and a low dielectric constant (2.43-2.58) at 1 MHz. The polymers show very good thermal stability, even up to 419 • C for 5% weight loss in synthetic air and a glass transition temperature of up to 230 • C. All poly(imide siloxane)s formed tough transparent films, with a tensile strength of up to 79 MPa, a modulus of elasticity of up to 1.38 GPa and elongation-at-break of up to 30%. Thermal, mechanical and dielectric properties of these polymers have been evaluated and compared with their non-siloxane analogues.

Solubility improvements in aromatic polyimides by macromolecular engineering

“…There are several reports on random fluorinated copoly(imide siloxane)s so far. [258][259][260][261][262][263][264] The exceptionally high solubility of the poly(imide siloxane)s could be ascribed to the presence of flexible aminopropyl linkages in the polymer backbone which imparts ease of penetration of solvent molecules in between the polymer chains and the presence of bulky -CF 3 groups reduces the chain packing density and hence enhances the solubility to a great extent. Thermal stability showed a decrease for the siloxane containing polymers compared to the respective homopolymers without siloxane units because of the weak aminopropyl linkages present in the polymer backbone.…”

A high performance polysiloxane-based single ion conducting polymeric electrolyte membrane for application in lithium ion batteries

“…Most SIPEs enable batteries to perform only at elevated temperatures with relatively low charge-discharge rates. [33][34][35] Based on this idea, we developed a methodology to synthesize a polysiloxane based single ion conducting gel polymer electrolyte with grafted bis(sulfonyl) imide groups via a hydrosilylation process. [30,31] It has been well demonstrated that ion migration occurs predominantly in amorphous opulent phase where transport properties, such as ionic conductivity, diffusivity and mechanical relaxation, are explicitly related to the segmental movement of polymers.…”

“…31 Unlike most of the polymers used as electrolytes, polysiloxanes, which are inherently amorphous in nature and possess very low T g with high thermal stability and good mechanical strength, may potentially serve as useful backbone polymers for designing SIPEs. [33][34][35] Based on this idea, we developed a methodology to synthesize a polysiloxane based single ion conducting gel polymer electrolyte with graed bis(sulfonyl) imide groups via a hydrosilylation process. Hydrosilylation is a catalyst assisted technique of adding Si-H bonds across unsaturated bonds.…”

Silicone containing copolymers: Synthesis, properties and applications

“…All copolymers displayed two T g values, one around -100 °C and the other in 129-184 °C range depending on the chemical structure and composition of the copolymers. All samples displayed excellent tensile properties withA c c e p t e d M a n u s c r i p t ultimate tensile strengths in 26 to 33 MPa range and elongation at break values of 120-130%(205, 206).PDMS-imide segmented and graft copolymers containing fluorinated imide hard segmentswere also investigated(198)(199)(200)(201)(202)(203)(204)(207)(208)(209)(210).Copolymers were prepared from aminopropyl terminated PDMS oligomers with <M n > values 900, 1,680 and 4,600 g/mol(203,211,212). High molecular weight copolymersobtained displayed microphase separated morphologies based on the DSC studies and good thermal stability.…”