What's inconvenient about mixing asphalt like a composite? Melt the binder
to 200-250F then turn in the solids,hand or mechanical, and cast. You could
mix and/or cast under vac too if max density/min void is so desired. I did
it for the first 10 years of my solids life, concurrent with my main liquid
work,1970's and we turned out professional level rocket motors where 20KFt
was a low end with a 3 stage flirted with 6 digits. Got pics. This was all
pre internet/social networking so word of our achievement spread slowly and
incompletely so many potential researchers were unaware of our work until
recent years.
On Wed, Jul 8, 2020 at 8:13 AM William Claybaugh <wclaybaugh2@xxxxxxxxx>
wrote:
There are today plenty of “rubbery” thermoplastics available. If we accept
somewhat lower performance then a professional propellant, it seems—in
principle—that making and casting solid propellant using a thermoplastic
binder should be relatively simple, as previous RRI experience w/ asphalt
suggests.
The problem for me has been figuring out a relatively safe process:
Dry mixing the ingredients and then melting seems—again, to me—too sporty.
Dry mixing the Al and binder seems safe enough; melting that and breaking
into pellets for later processing also seems safe up to the point that AP
is added.
Any thoughts as to how to cast a thermoplastic grain w/o having to mix dry
fuel and oxidizer before melting?
Bill