Ken, According to my references, PPG propellants have an ISP of 262 @ 84%
solids loading and 18% aluminum powder. Heat of formation is -90.0 Kcal/100
grams and C 5.1184, H 10.3371, O 1.7563. PPG propellant was used in the Hawk
missile originally. Troy accurately reported that PPG has moisture sensitivity
problems in mixing and casting. Propellant using this binder fell into disuse
because it absorbed enough moisture over time to dissolve some of the ammonium
perchlorate thus forming an ionic solution that resulted in moisture
imbrittlement due to polymer chain breakage thus causing the finished
propellant to lose its elongation abilities. Barry Sent from my Sprint Tablet.
-------- Original message --------From: roxanna Mason
<rocketmaster.ken@xxxxxxxxx> Date: 7/9/20 20:00 (GMT-05:00) To:
arocket@xxxxxxxxxxxxx Subject: [AR] Re: Amateur thermoplastic binder solids No
you're not, my computer somehow put my response in drafts and it just turned
up.I am curious if PPG does indeed have an unexpectedly high c*.On Thu, Jul 9,
2020 at 4:50 PM Anthony Cesaroni <anthony@xxxxxxxxxxx> wrote:I missed that. My
bad. Anthony J. CesaroniPresident/CEOCesaroni Technology/Cesaroni
Aerospacehttp://www.cesaronitech.com/(941) 360-3100 x1004 Sarasota(905)
887-2370 x222 Toronto From: arocket-bounce@xxxxxxxxxxxxx
<arocket-bounce@xxxxxxxxxxxxx> On Behalf Of roxanna MasonSent: Thursday, July
9, 2020 7:33 PMTo: arocket@freelists.orgSubject: [AR] Re: Amateur thermoplastic
binder solids We were talking about two different applications, the PG for a
heat transfer medium for the asphalt double boilerand the PPG as a fuel/binder.
On Thu, Jul 9, 2020 at 7:44 AM Anthony Cesaroni <anthony@xxxxxxxxxxx>
wrote:Propylene glycol and polypropylene glycol (PPG) are two different but
related chemicals. Anthony J. CesaroniPresident/CEOCesaroni
Technology/Cesaroni Aerospacehttp://www.cesaronitech.com/(941) 360-3100 x1004
Sarasota(905) 887-2370 x222 Toronto From: arocket-bounce@xxxxxxxxxxxxx
<arocket-bounce@xxxxxxxxxxxxx> On Behalf Of ken masonSent: Wednesday, July 8,
2020 7:40 PMTo: arocket@freelists.orgSubject: [AR] Re: Amateur thermoplastic
binder solids Exactly DH, non toxic Propylene Glycol was my thoughts, available
at auto parts stores as antifreeze coolant and in my cars
radiators.Theoretically water under pressure with a calibrated relief valve so
the temp can never exceed a safe temp. Depending on the grade of asphalt no
relief valve just melt/mix at the boiling point of pure water. I tested my
asphalt sample at the BP of water, 219F at my elevation, and it was at a
workable viscosity. I don't have a Haake viscometer like at Edwards but it was
about like R-45 at RT maybe a bit thinner. K On Wed, Jul 8, 2020 at 4:32 PM DH
Barr <dhbarr@xxxxxxxxx> wrote:For the amateur with a double boiler and
appropriate ratios of alcohol, water, and glycol; one should be able to
precisely target arbitrary temperatures across a fairly wide range ( boiling
point of pure alcohol through boiling point of pure glycol ).On Wednesday, July
8, 2020, Troy Prideaux <troy@xxxxxxxxxxxxxxxxxxxxx> wrote:> IIRC it's a
technique also employed for gelatine processing in capsule> manufacture for
drugs. I vaguely recall gelatine has quite a narrow window> of temperature
where it will stay liquid - around 60deg C or thereabouts; so> a heating jacket
is employed using steam, but due to the lower temperature,> its pressure is
reduced to near vacuum to ensure boiling and uniform steam> dispersion
throughout the heating jacket.> Speaking of vacuums, you can also utilise a
partial or full vacuum to> increase the safety margin of propellant processing
utilising elevated> temperatures ie. it's much harder to ignite propellants
under vacuum> conditions.>> Troy>>> -----Original Message----->> From:
arocket-bounce@xxxxxxxxxxxxx [mailto:arocket-bounce@xxxxxxxxxxxxx]> On>> Behalf
Of Henry Spencer>> Sent: Thursday, 9 July 2020 7:19 AM>> To: Arocket List
<arocket@xxxxxxxxxxxxx>>> Subject: [AR] Re: Amateur thermoplastic binder
solids>>>> On Wed, 8 Jul 2020, William Claybaugh wrote:>> > My sources say AP
ignites a little above 400 degrees F so a binder>> > that forms a low viscosity
fluid at around the BP of water will in>> > theory work fine if there is no
possibility of hot spots.>>>> If you can find something that works *at* the
boiling point of water, you> can>> use steam heat (with a steam source that
heats the water, not the>> steam) to ensure it just can't go any hotter.>>>>
(This technique is, or was -- my info may be out of date -- widespread for>
filling>> munitions with TNT, which is a fairly-stable liquid at 100degC.>>
That helpful property is one reason why TNT became so popular.)>>>> > If I were
going in that direction I would want to automate the mixing>> > rather than
stand over an open pot of hot binder, AP, and Al, stirring.>>>> If one must
pre-fix fuel and oxidizer :-), especially hot, doing it from a> distance>>
makes a whole lot of sense.>>>> Henry>>>