Properties and Applications of Poly-3,3-Bis Chloromethyl Oxetane

PolyBCMO is one of the large-scale production polymers based on the cationic ring-opening polymerization. Production was started in the mid-fifties by Hercules Co. (Penton ) but it was discontinued in the late 70 s. There are also indications of its production in the USSR (Pentaplast ). 

PolyBCMO exhibits an excellent combination of physical-chemical-processing characteristics rendering it a competitive thermoplastic material (engineering plastic). 

In particular, it has a combination of relatively high melting point, outstanding thermal stability and unusually good chemical resistance (e.g. stable to cone. H2S04 up to 120 °C) 28). Thus, Penton has found numerous applications for the construction of chemical equipment. 

PolyBCMO is a light-coloured thermoplastic with a crystalline melting point of 181 °C. Its mechanical properties are close to those of Nylon 6 (impact strength is poorer) as well as to those of low density polyethylene. 

The crystalline polymer may exist in two forms a and p. The higher melting cx-form, having an orthorhombic unit cell, is formed when the polymer crystallizes out of the melt or solution. The thermodynamically unstable P-form occurs when quenched amorphous polymer is annealed above the glass-transition temperature annealing at 115 °C transforms the P-form into the a-form. The average size of lamellae formed in isothermal crystallization is 1000-2000 A in lateral dimensions, with a thickness of 100 A. 

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