Synthesis and characterization of new organosoluble poly(ether imide)s derived from various novel bis(ether anhydride)s - Polyimides and Other High Temperature Polymers - page 54

The diamine containing noncoplanar 2,2'-dimethyl-4,4'-biphenylene group
(DBAPB, Scheme IV) was obtained. The yield was 80%; m.p. 138-139 C. The

IR spectrum (KBr) exhibited absorptions at 3324 and 3406 cm -1 (N-H), and 1226
cm -1 (C-O-C). Elemental analysis calcd for C 26 H 24 O 2 N 2 : C, 78.76%; H, 6.10%; N,
7.07%; found: C, 78.41%; H, 6.34%; N, 7.10%.

°

2.4. Polymerization procedures (Schemes III and V) [17, 38-43, 48]
2.4.1. Synthesis of poly(ether imide)s [38-43]
To a stirred solution of diamine (Such as 5a or 5b, Scheme III) (1.1 mmol) in
DMAc (5 mL), bis(ether anhydride) (Such as 4A, 4B, 4C, 4D, 4E or 4F, Scheme
III) (1.1 mmol) was gradually added. The mixture was stirred at room temperature
for 2 hrs under argon atmosphere to form the poly(ether amic acid) precursor
(Such as A-6a, B-6a, C-6a, D-6a, E-6a, F-6a, A-6b, B-6b, C-6b, D-6b, E-6b or
F-6b, Scheme III). Chemical imidization was carried out by adding an extra 3 mL
of DMAc, 1 mL of acetic anhydride and 0.5 mL pyridine into the above-
mentioned poly(ether amic acid) precursor (Such as A-6a, B-6a, C-6a, D-6a, E-
6a, F-6a, A-6b, B-6b, C-6b, D-6b, E-6b or F-6b, Scheme III) solution with stir-
ring at room temperature for 1 h, and then heating at 100 C for 3 hrs. The homo-

geneous solution was subsequently poured into methanol and the yellow solid
precipitate was filtered off, washed with methanol and hot water, and then dried at
100

°

C for 24 hrs to afford poly(ether imide)s (Such as m-tert, TP-tert, Tcardo-
tert, TMA-tert, Cyclo-tert, Phcardo-tert, m-m, TP-m, Tcardo-m, TMA-m,
Cyclo-m or Phcardo-m, Scheme III) [38-43].
2.4.2. Synthesis of polyimides derived from various commercial dianhydrides [17, 48]
To a stirred solution of 1.25 mmol of diamine (Such as tert and m, Scheme V) in
8 mL of DMAc, 1.25 mmol of dianhydride (Such as PMDA, BPDA, ODPA,
BTDA, 6FDA and SDPA, Scheme V) was gradually added. The mixture was
stirred at room temperature for 2-4 hrs under argon atmosphere to form the
poly(amic acid). From this solution a film was cast onto a glass plate and heated
(8 hrs at 80

°

C) to
convert the poly(amic acid) into polyimide film. Chemical cyclodehydration was
also carried out by adding DMAc, and an equimolar mixture of acetic anhydride
and pyridine into the above-mentioned poly(amic acid) solution with stirring at
room temperature for 1 hr, and then heating at 100

° C, 1 hr at 120 ° C, 1 hr at 150 ° C, 2 hrs at 200 ° C, 1 hr at 250 °

C for 3 hr. The polymer solu-
tion was poured into methanol. The precipitate was collected by filtration,
washed thoroughly with methanol and hot water, and dried at 100

°

C under vac-
uum. A series of polyimides derived from various commercial dianhydrides
(Such as PMDA-tert, BPDA-tert, ODPA-tert, BTDA-tert, 6FDA-tert, SDPA-
tert, PMDA-m,

°

BPDA-m, ODPA-m, BTDA-m, 6FDA-m and SDPA-m,

Scheme V).