Anyone know how to make polyepichlorohydrin?

[megalomania]

I am currently doing research on energetic polymeric binders and plasticizers, specificially glycidyl azide polymer. GAP requires a starting material called PECH (polyepichlorohydrin) which is the copolymer of epichlorohydrin and glycerol. I have done a CAS database search of every journal there is and had no luck finding a synthesis. The only Internet hits I found were just reaction equations. Even the reference article I obtained from my source about GAP didn’t actually have a synthesis although it said it would.

I am not naive enough to imagine all I have to do is mix glycerol and epichlorohydrin under reflux, I know it can’t be that easy. I don’t really know that much about polymerization chemistry, so I don’t know about the proper resources to search. I am looking for reaction conditions, ways to get target molecular weights, purification, and that sort.

I suspect PECH is a very old polymer known for over 100 years, and that may be why there is no available literature on its synthesis. If anybody knows any good books on synthesizing polymers, please suggest one.

<small>[ April 18, 2002, 08:39 PM: Message edited by: megalomania ]</small>

[cutefix]

There is an example;check at at USPTO #6,323,352
"Preparation of a polyepichlorohydrin with a hydroxyl terminal group of formula (II) with R.sub.1 =--(CH.sub.2).sub.2 --.

380 g of 1,2-dichloroethane (solvent), 62.85 g (0.78 mol) of 2-chloroethanol (initiator) and 5.35 g (3.8.times.10.sup.-2 mol) of boron trifluoride etherate (catalyst) are introduced into a 500 ml jacketed reactor equipped with a mechanical stirrer, a temperature probe and a water-cooled reflux condenser.

The mixture is brought to 30.degree. C. and then 650 g (7.03 mol) of epichlorohydrin are added dropwise over 6 hours while maintaining the temperature at 30.degree. C.

After the reaction, the reaction mixture is poured into 0.75 l of water comprising 15 g of K.sub.2 CO.sub.3.

After stirring for approximately 20 min and then separating by settling, the aqueous phase is removed and then the organic phase is washed a second time with water to which K.sub.2 CO.sub.3 has been added and then a third time with pure water.

After evaporating the solvent, 685 g (96% yield) of a colourless liquid are collected, for which the main characteristics measured are as follows: "

Hydroxyl level: 1.11 eq OH/kg

[Azazel]

hey dude thats cool :)
what year are you doing in university/college ???

[vulture]

It's available through polymerisation of epichlorhydrine with Aluminiumtriethyl ((C2H5)3Al)/H2O/Acetylacetone as katalysator.

It's used in automibile industry to produce flexible tubes, for hazmat suits,....