Hydrolytic binder degradation

Oxidative Binder and Hydrolytic Binder Degradation Aging Studies... 

Reliable data in the literature for the stress versus strain properties of composite propints are exceedingly difficult to find. Since the binder chemical properties and curing additions are susceptible in many cases to hydrolytic degradation, the exact formulations under test should be specified. Additionally, the binder to oxidizer adhesion properties are dependent upon particle size distribution used in the pro-pint. This should be specified and in almost all literature sources unearthed, it remained unknown. As some of these data show, the manner of conducting the test and control of such... 

The experimental data for molecular weight and L/Lo agree well with the hydrolytic degradation predictive model for Estane as shown in Figure 10. Ongoing experimental work validating the Estane hydrolysis model for Estane binder will contribute to providing a robust lifetime prediction for PBX 9501 explosives. 

The potential value of the NMR MOUSE for detecting hydrolytic degradation in Estane was demonstrated. This technique is sensitive to increased chain mobility in the degraded Estane and showed a good correlation of the relaxation time with a decrease in molecular weight. Additional studies of aged Estane/NP/Irganox binder are underway to evaluate use of this instrument. 

In 1962, Bowman showed that this polymer could be used as a binder for solid propellants [23]. Poly(glycolic acid) (PGA)was found easily thermally degraded [24] and its poor thermal and hydrolytic stabilities were problematic for any permanent appUcation. Choju et al. [25] mentioned that this PGA homopolymer is an unstabiUzed polymer and weight loss under heating begins at 240 °C [25]. 

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