Cyclobutane tetracarboxylic dianhydride

Poly(amic acids) were prepared by the ambient temperature condensation of 1,2,3,4-cyclobutane tetracarboxylic dianhydride with selected aromatic diamines. When the poly(amic acids) and liquid crystal alignment agents y-butyrolactone and A-methyl-pyrrolidone were spin-coated and cured onto an inert surface, the polyimide was effective as a liquid crystal aligner. 

A reaction flask was charged with 3,5-di-dodecyloxybenzyl-3,5-diamino-benzoate-diamine (0.75 mmol), 1, 2, 2 -bis[4-(4-aminophenoxy)phenyl]propane (4.25 mmol), 1,2,3,4-cyclobutane tetracarboxylic dianhydride (5.00 mmol), and A-methylpyrrol-idone (17.69 g) and then stirred at ambient temperature until a 15 wt% solid content polyimide precursor solution was obtained. 

TABLE 3. Results of water and methylene/iodine repellency testing of polyimide films obtained by reacting 1,2,3,4-cyclobutane tetracarboxylic dianhydride with amines described in Table 1. 

Y. Lu, Z. Hu, Y. Wang, Q.X. Fang, Organosolu-ble and light-colored fluorinated semialicyclic polyimide derived from 1,2,3,4-cyclobutane-tetracarboxylic dianhydride, J. Appl. Polym. Sci. 125 (2) (2012) 1371-1376. 

Figure 6.26 Photodimerization of maleic anhydride (44) to cyclobutane tetracarboxylic dianhydride (45) and the experimental setup for the ultrasound-assisted photodimerization...

---