FR2707979A1 - Glycidyl azide polymer containing azide end groups, and its preparation - Google Patents

Abstract

Glycidyl azide polymer containing azide end groups, and its preparation. A glycidyl azide polymer, containing azide endings, of formula is prepared by using a single-stage process according to which an alpha -(2-chloroethyl)- omega -benzenesulphonylpolyepichlorohydrin ( alpha -(2-chloroethyl)- omega -phenylsulphonylpolyepichlorohydrin) (n having the value 2 to 10) is reacted with sodium azide in a polar solvent, such as dimethyl sulphoxide. Application: energising plasticiser for propellants.

Description

The present invention relates to an energetic composition

  getic and it targets more particularly a polymer

  of glycidyl azide, terminated at each of its two ends

  mites by an azide group, as well as a process for producing

re this compound.

  We generally formulate solid propellants

  so as to include an oxidant and fuel, all with suitable binders and plasticizers, in order to amplify the physical and chemical characteristics of the propellants. Most propellant systems use

  binders and plasticizers containing energetic groups

  such as nitro (-NO2), fluorodinitro

  (FC (NO2) 2-), difluoro-amino (-NF2), as well as others.

  These plasticizing azides provide extra energy to a propellant system, since each azido group present provides approximately the system

kcal / mole (355.9 kJ / mole).

  A polymer of azide, terminated by a functional group-

  nel, is taught by Wilson and his collaborators in the patent application of the United States of America n 56,026,

  filed June 1, 1987. Another energetic azide polymer

  tick is described in US-A-4,268,450, to which

  will be able to refer. In contrast to the present invention

  tion, the two aforementioned polymers, and the process for obtaining them, can be distinguished in part by the initiation groups and the repeating patterns present in the materials.

  and in the final products. The present invention

  tion offers a one-step synthesis, giving with

  high yield a glycidyl azide polymer, termi-

  born by azide groups, which meets the requirements of many propellant systems and is particularly useful as an energy plasticizer for propellants and

explosives.

  It can therefore be confirmed that the present invention provides an energetic polymer comprising a polymer

  aliphatic terminated by azide groups.

  The objects of the present invention are therefore, no-

in particular, to provide:

  a composition useful for the formulation of proper-

  solid gols, explosives and the like; an energy plasticizer, which is an azide polymer whose two ends are terminated by azide groups; and

  a one-step process for producing plas-

  tifier consisting of an azide polymer terminated by

azide groups.

  The glycidyl azide polymer, terminated with azide groups, of the present invention is characterized in Table 1 below:

TABLE 1

  Name: glycidyl azide polymer, terminated by azide groups (or glycidyl azide polymer azide) Structure N3CH2CH2 OCH2CH OCH2CHN3

CH 2N3 CH2N3

  Formula C14H24 N1804 Molecular weight 508 Elemental analysis: CHN Calculated 33.07 4.72 49.61 Found 34.38 5.14 49.30 Infrared spectrum: N3 (4.7 1) Appearance: light yellow liquid Index of refraction: 1.5138 at 25 C Density: 1.27 g / cm3 at 25 C Freezing point: -56 C Calorimeter examination at the start of differential heat release: 205 C Weight loss: 0.48% after 48 h at 74 C Table 1 (continued) Sensitivity to impact: 4.52 Nm (40 in-lDj

Electro- sensitivity

  static:> 12.5 joules sensitivity to friction:> 0.35 Nm (> 36 kg.cm) AHf (estimated value) + 1402.65 kJ / mole (+ 335 kCal / mole) Classification for explosive of class B (shipping solution: 25-35% in CH2Cl2 We can produce the glycidyl azide polymer, terminated by azide groups, of general formula (1)

N3CH2CH2 OCH2CH OCH2CHN3

CH2N3 CH2N3

n-1

  by the one-step process constituting to do

  gir an a- (2-chlorethyl) --- benzenesulfonyl polyepichlorhy-

  drine of general formula (2) ClCH2H2 - OCH2CH i S03C6H5

L 2

  n with sodium azide in a polar solvent such as dimethylsulfoxide (DMSO), the index n appearing in formulas (1) and (2) representing an integer ranging from 2 to 10. The polymer is particularly preferred in the formula

of which n is 3.

  The following example illustrates the invention.

EXAMPLE

  In a suitable reactor, 2750 ml of

  dimethyl sulfoxide, under a nitrogen purge stream, up to

  only at 70 C. 2090 g (32.15 moles) of sodium azide are added over 15 minutes. This mixture is then heated to 95 C

  and 2511.2 g (26.79 moles) of a- (2-

  chlorethyl) -O-benzenesulfonyl polyepychlorohydrin. It is not necessary to apply additional heating during the addition, in order to maintain the temperature at

  a value between about 95 and about 1000C.

  Once the addition is complete, the reaction mixture is heated for an additional 12 hours at a temperature between 95 and approximately 100 C. The reaction mixture is then cooled by adding 6.5 l of water to it. The resulting organic phase is separated, washed four times with

  ten liters of hot water, dilute until you get a solution

  tion at 20% in methylene chloride, dried over anhydrous sodium sulfate, and passed to

  through a column of 2000 g of silica gel. The concentration

  tion of the solution gives 1896.5 g (83.9%) of the polymer

  of azide-terminated glycidyl azide, the properties of which

  These are described in Table 1 above.

  It should be noted that the quantities, temperatures, times, solutions, devices and

  means of addition, submersion and drowning procedures

  age, number of washes, extraction and

  which have been used or can be used

  all to meet specific requirements

  and to match specific reactions. The parameters

  very mentioned here are simply presented as

representative example.

  It goes without saying that many modifications and variations are possible, for the implementation of the

  present invention in the light and in the context of teach-

above.

Claims (3)

  1. Polymer of glycidyl azide, terminated by azide groups, of general formula: (1) N3CHC FOHH1CH2OCH2CH OCCHN3 CH2N3 CH2N3 n-1   produced by the one-step process consisting   both to react an a- (2-chloroethyl) -i-benzenesulfoni-   than polyepichlorohydrin of general formula: (2) CiCH2CH2 -OCH2CH I SO3C H CH2N3   n with sodium azide in a polar solvent, the index n representing, in formulas (1) and (2), a number integer from 2 to 10.   2. A glycidyl azide polymer with terminal azide groups according to claim 1, characterized in that it is obtained by the process indicated in claim 1 and in which the polar solvent which is used for the   production of the polymer is dimethyl sulfoxide.   3. A glycidyl azide polymer with azide endings, characterized in that it corresponds to the formula general: - N3CH2CH2 OCH2CH OCH2CHN3 CH2N3 C2N3