Gas generating composition and method of preparing compression molded articles therefrom

• US 3,920,575 A
• Filed: 02/21/1974
• Issued: 11/18/1975
• Est. Priority Date: 03/03/1973
• Status: Expired due to Term

• Current Assignee: Ikuo Harada, Masaaki Shiga, Tadamasa Harada, Takehiko Shiki
• Original Assignee: Ikuo Harada, Masaaki Shiga, Tadamasa Harada, Takehiko Shiki
• Inventors: Shiga, Masaaki, Shiki, Takehiko, Harada, Ikuo, Harada, Tadamasa
• Primary Examiner(s): Padgett, Benjamin R.
• Assistant Examiner(s): Leland, David
• Application Number:
  US05/444,607
• Time in Patent Office: 635 Days
• Field of Search: 252/350,188.3 149/35 264/3C,DIG.5 280/15AB
• US Class Current: 149/35
• CPC Class Codes: C06B 35/00 Compositions containing a metal azide
• CPC Class Codes: C06D 5/06 by reaction of two or more solids

Abstract

A gas generating composition comprising: I. at least one metal azide compound selected from the group consisting of alkali metal azides, alkaline earth metal azides and hydroxy metal azides having the general formula M(OH)m(N3)n WHEREIN M represents magnesium, calcium, strontium, zinc, boron, aluminum, silicon, tin, titanium, zirconium, magnesium, chromium, cobalt or nickel; (M + N) REPRESENTS AN ATOMIC VALENCY OF M; and m and n represent a positive number, respectively, II. at least one oxidizing agent or a combustion composition comprising at least one oxidizing agent and at least one reducing agent; and III. at least one compound selected from the group consisting of a compound of the formula (Al2O3)p(MxO)q(SiO2)r.sH2O wherein M represents lithium, sodium, potassium, strontium, magnesium or calcium; x is 1 or 2; p and q represent zero or a positive number, respectively but p and q are not zero simultaneously; r is a positive number; and s is zero or a positive number, POTASSIUM CHLORIDE, POTASSIUM BROMIDE, CALCIUM CHLORIDE, SODIUM BROMIDE, STRONTIUM CHLORIDE AND STRONTIUM HYDROXIDE, IN AN AMOUNT OF FROM ABOUT 0.5 TO 30 PARTS BY WEIGHT BASED ON 100 PARTS BY WEIGHT OF THE TOTAL OF THE METAL AZIDE COMPOUND (I) and the oxidizing agent or the combustion composition (II). The composition generates non-toxic molecular nitrogen gas and is especially effective for producing compression-molded articles such as tablets.

Claims

1. A GAS GENERATING COMPOSITION COMPRISNG:

2. A gas generating composition according to claim 1, wherein the metal azide compound is selected from the group consisting of strontium azide, barium azide and sodium azide.

3. A gas generating composition according to claim 1, wherein the oxidizing agent is selected from the group consisting of lithium perchlorate, potassium perchlorate, ammonium perchlorate, sodIum perchlorate, potassium chlorate, potassium bromate, potassium nitrate, barium nitrate, lithium peroxide, sodium peroxide, potassium peroxide, barium peroxide, lead peroxide, manganese dioxide, ferric oxide, ferrosoferric oxide, lead oxide, chromium trioxide and trilead tetraoxide.

4. A gas generating composition according to claim 1, wherein the reducing agent is selected from the group consisting of zirconium, magnesium, boron, aluminum, silicon, ferro-silicon, titanium and manganese.

5. A gas generating composition according to claim 1, wherein the compound of the formula (Al2O3)p(MxO)q(SiO2)r.sH2O is selected from the group consisting of (Na2O)q(SiO2)r.sH2O, (K2O)q(SiO2)r.sH2O, (Li2O)q(SiO)r.sH2O, (Al2O3)p(SiO2)r.sH2O, (MgO)q(SiO2)r.sH2O, (Al2O3)p(MgO)q(SiO2)r.sH2O, (Al2O3)p (K2O)q(SiO2)r.sH2O, (Al2O3)p(Na2O)q(SiO2)r.sH2O and (Al2O3)p(CaO)q(SiO2)r.sH2O wherein p, q and r, each is a positive number.

6. A method of preparing gas generating compression-molded articles which comprises adding about 7 to 300 parts by weight of water to about 100 parts by weight of a gas generating composition comprising:

I. at least one metal azide compound selected from the group consisting of alkali metal azides, alkaline earth metal azides and hydroxy metal azides having the general formula M(OH)m(N3)n wherein M represents magnesium, calcium, strontium, zinc, boron, aluminum, silicon, tin, titanium, zirconium, magnesium, chromium, cobalt or nickel;

(m + n) represents an atomic valency of M; and

m and n represent a positive number, respectively, II. a least one oxidizing agent or a combustion composition comprising at least one oxidizing agent and at least one reducing agent; and

III. at least one compound selected from the group consisting of a compound of the formula (Al2O3)p(MxO)q(SiO2)r.sH2O wherein M represents lithium, sodium, potassium, strontium, magnesium or calcium;

x is 1 or 2;

p and q represent zero or a positive number, respectively but p and q are not zero simultaneously;

r is a positive number; and

s is zero or a positive number, potassium chloride, potassium bromide, calcium chloride, sodium bromide, strontium chloride and strontium hydroxide, in an amount of from about 0.5 to 30 parts by weight based on 100 parts by weight of the total of the metal azide compound (I) and the oxidizing agent or the combustion composition (II), forming the resulting mixture into granules, drying the granules and subjecting the dried granules to compression molding.

7. A method according to claim 6, wherein about 7 to 300 parts by weight of an organic medium soluble in or miscible with water selected from the group consisting of aliphatic alcohols having 1 to 6 carbon atoms, aliphatic ketones having 3 to 5 carbon atoms and aliphatic ethers having 2 to 5 carbon atoms is employed together with water.

8. A method according to claim 7, wherein the gas generating composition contains about 0.1 to 5 parts by weight of an alkaline compound selected from the group consisting of lithium hydroxide, sodium hydroxide, potassium hydroxide, strontium hydroxide, barium hydroxide, lithium carbonate, sodium carbonate, potassium carbonate, strontium carbonate, lithium hydrogenbicarbonate, sodium hydrogenbicarbonate and potassium hydrogenbicarbonate.

9. A method according to claim 6, wherein the compound of the formula (Al2O3)p(MxO)q(SiO2)r.sH2O is selected from the group consisting of (Na2O)q(SiO2)r.sH2O, (K2O)q(SiO2)r.sH2O, (Li2O)q(SiO2)r.sH2O, (Al2O3)p(SiO2)r.sH2O, (MgO)q(SiO2)r.sH2O, (Al2O3)p(MgO)q(SiO2)r.SH2O, (Al2O3)p(K2O)q(SiO2)r.sH2O, (Al2O3)p(Na2O)q(SiO2)r.sH2O and (Al2O3)p(CaO)q(SiO2)r.sH2O wherein p, q and r, each is a positive number.