Substituted ammonium salt of 1,5′-bitetrazole

BACKGROUND OF THE INVENTION

The present invention relates to novel 1,5′-bitetrazole compounds and processes for their production.

The present invention also relates to gas generating agents containing the 1,5′-bitetazole compounds.

The present invention further relates to foaming agents for precision molding of resins, foaming agents for reducing weight of molded articles, smoking agents for effectively diffusing chemicals such as agricultural chemicals or insecticides, and air bag gas generating agents.

It is difficult td mold crystalline resins into the shape defined by a mold, since they crystallize and shrink upon cooling after molding. Conventionally, for precision molding of crystalline resins, apparent shrinkage is empirically inhibited by using specially devised molds, which, however, cannot accomplish complete precision molding. Accordingly, additional techniques for further reducing shrinkage of molded articles are employed, which include physical blowing of gas into the core portion of molded articles (Japanese Examined Patent Publications Nos. 41264/1973 and 14968/1982), and addition of chemical foaming agents (Japanese Unexamined Patent Publications Nos. 129563/1975, 12864/1978 and 61435/1981, and U.S. Pat. No. 4,871,861). In conventional techniques, azodicarbonamide (ADCA) has been used widely for a long period of time, mainly for foam molding of resins.

ADCA, although utilized widely as a gas generating agent, is not wholly satisfactory for use in precision molding or high-foam molding for weight reduction, because it has too broad a decomposition temperature range relative to the molding temperature and causes air bubbles on the surface of molded articles, which impair the appearance. Moreover, decomposition gases and residues of ADCA contain toxic substances such as ammonia, biurea or isocyanuric acid, and thus are harmful to humans and animals and the environment. Further, the decomposition residue contaminates molds, decreasing the molding efficiency and yield of molded articles.

To solve the above problems, use of tetrazoles as gas generating agents was proposed. Tetrazoles, which decompose completely, are free from the above problems. However, since high decomposability means low stability, tetrazoles are highly sensitive to friction or other physical factors, lacking handling safety.

Further, although air bag gas generating agents and smoking agents are required to be harmless to humans and animals, safe, and odorless, conventional air bag gas generating agents and smoking agents do not fully satisfy these requirements.

SUMMARY OF THE INVENTION

An object of the invention is to provide a novel 1,5′-bitetrazole compound which is highly sensitive only to temperature and which decomposes sharply, i.e., decomposes in a narrow temperature range, and generates a nontoxic gas.

Another object of the invention is to provide a gas generating agent which is highly sensitive only to temperature and which decomposes sharply and generates a nontoxic gas.

The present inventors did extensive research to achieve the above objects and directed their attention to 1,5′-bitetrazole which leaves substantially no residue upon decomposition. They found that ammonia or amine can be used to reduce the physical sensitivities of 1,5′-bitetrazole. The present invention has been accomplished based on this novel finding.

The present invention provides the following 1,5′-bitetrazole, processes for their production, and gas generating agents containing the.

1. A 1,5′-bitetrazole represented by the formula (1):

wherein Tz

31

represents

R

1

, R

2

and R

3

are the same or different and each represent a hydrogen atom; C

1-10

alkyl which may be substituted by amino, di(C

1-4

alkyl)amino, C

1-8

alkoxy, hydroxy or phenyl; C

3-20

alkenyl; phenyl; —C(═NH)NH

2

; —C(═NH)NHNH

2

; —C(═NH)NHCN; triazolyl; amino; carbamoyl; triazinyl which may be substituted by amino and methyl; —NHCS;

or —R

4

—NH

3

+

Tz

−

wherein Tz

−

is as defined above, R

4

represents a single bond, C

2-6

alkylene, phenylene, —CO— or

when R

1

is a hydrogen atom, R

2

and R

3

may be taken together with the nitrogen atom to which they are attached to form a 5- to 7-membered saturated heterocycle; when R

1

is a hydrogen atom, R

2

and R

3

may be taken together to form

and R

1

, R

2

and R

3

may be taken together to form

2. A process for producing a 1,5′-bitetrazole amine salt according to Item 1 comprising the step of reacting 1,5′-bitetrazole or its alkali salt with ammonia or an or its carbonate or halide, the amine being represented by the formula:

R

5

R

6

R

7

N (2)

wherein R

5

, R

6

and R

7

are the same or different and each represent a hydrogen atom; C

1-10

alkyl which may be substituted by amino, di(C

1-4

alkyl)amino, C

1-8

alkoxy, hydroxy or phenyl; C

3-20

alkenyl; phenyl; —C(═NH)NH

2

; —C(═NH)NHNH

2

; —C(═NH)NHCN; triazolyl; amino; carbamoyl; triazinyl which may be substituted by amino and methyl; —NHCS;

or —R

8

—NH

2

wherein R

8

represents a single bond, C

2-6

alkylene, phenylene, —CO— or

when R

5

is a hydrogen atom, R

6

and R

7

may be taken together with the nitrogen atom to which they are attached to form a 5- to 7-membered saturated heterocycle; when R

5

is a hydrogen atom, R

6

and R

7

may be taken together to form

and R

5

, R

6

and R

7

may be taken together to form

3. A gas generating agent containing a 1,5′-bitetrazole according to Item 1.

4. A foaming agent for molding resins, which contains a 1,5′-bitetrazole according to Item 1.

5. An air bag gas generating agent containing a 1,5′-bitetrazole according to Item 1.

6. A smoking agent for diffusing chemicals, which contains a 1,5′-bitetrazole according to Item 1.

The 1,5′-bitetrazole amine salt of the invention comprises 1,5′-bitetrazole, and ammonia or an amine.

Useful amines include monomethylamine, monoethylamine, n-propylamine, isopropylamine, n-butylamine, sec-butylamine, t-butylamine, n-hexylamine, n-octylamine, 2-ethylhexylamine, oleylamine, allylamine, 3-dimethylaminopropylamine, 3-dibutylaminopropylamine, 3-methoxypropylamine, 3-ethoxypropylamine, 2-ethylhexyloxypropylamine, methyliminobispropylamine, cyclohexylamine, aniline, benzylamine, phenethylamine, dicyandiamide, guanidine, aminoguanidine, aminotriazole, monoethanolamine and like primary monoamines; ethylenediamine, hexamethylenediamine, phenylenediamine, xylenediamine, xylylenediamine, acetoguanamine, hydrazine, urea, carbohydazide, thiocarbohydrazide, N-acetyl-m-phenylenediamine, 2,4-diamino-6-methyl-symtriazine, 1,4-bis(3-aminopropyl)piperazine and like primary diamines; melamine and like primary triamines; dimethylamine, diethylamine, dicyclohexylamine, di-2-ethylhexylamine, diethanolamine, piperazine, piperidine, diphenylamine and like secondary monoamines or secondary diamines; and trimethylamine, triethylamine, N,N,N′,N′-tetramethylethylenediamine, hexamethylenetetramine, pyridine, N,N-dimethylaniline, N,N-dimethylcyclohexyl-amine, triethanolamine and like tertiary amines.

The process for producing the novel 1,5′-bitetrazole of the invention comprises the steps of dissolving 1,5′-bitetrazole or its alkali metal salt in water, an alcohol (preferably a C

1-3

alcohol) or dimethylformamide (DMF), and adding ammonia or the above amine or its carbonate or halide in an equivalent amount relative to the 1,5′-bitetrazole or its alkali metal salt, followed by stirring. When an alkali metal salt of 1,5′-bitetrazole and an amine halide are used, it is preferable to select such a combination that the alkali metal halide produced as a byproduct is soluble in water, alcohol or DMF, so that 1,5′-bitetrazole can be easily obtained by collecting crystals by filtration.

The reaction is carried out at preferably 0 to 100° C., more preferably 20 to 60° C., for a period of preferably 0.5 to 10 hours, more preferably 1 to 3 hours.

The 1,5′-bitetrazole is a novel substance which has low detonability and high stability against physical shocks, i.e., low sensitivity to impact or friction. Unlike ADCA, the 1,5′-bitetrazole is free from the problems of toxic decomposition gas or residue, since it decomposes completely and generates a nontoxic gas. Therefore, it is usable as an air bag gas generating agent or a smoking agent. Moreover, since the compound decomposes sharply, its use as a foaming agent, for example in injection molding, enables formation of a smooth skin layer which cannot be obtained by use of ADCA or like substance, and achieves precision molding free from sinkmarks or warpage.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1

shows the result of differential thermal analysis of 1,5′-bitetrazole guanidine salt as an embodiment of the invention.

FIG. 2

shows the infrared absorption spectrum of 1,5′-bitetrazole guanidine salt as an embodiment of the invention.

FIG. 3

shows the result of NMR analysis of 1.5′-bitetrazole guanidine salt as an embodiment of the invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The following examples are intended to illustrate the present invention in further detail.

EXAMPLE 1

A 500-ml, four-necked flask equipped with a stirrer and thermometer was set in an oil bath and charged with 50 g (0.362 moles) of 1,5′-bitetrazole (molecular weight: 138.09), followed by addition of 300 ml of water. The mixture was heated to 40° C., and 15.6 g (0.181 moles) of piperazine (molecular weight: 86.14) was added with stirring. Simultaneously with addition of the piperazine, crystals formed and the reaction mixture became pale yellow. The reaction mixture was cooled to room temperature with stirring, and subjected to suction filtration using a No. 2 filter paper, whereby 1,5′-bitetrazole piperazine salt (molecular weight: 362.32) was obtained in a yield of 85%.

EXAMPLE 2

2 g of 1,5′-bitetrazole was measured out into a 50-ml beaker, and dissolved by addition of 50 ml of methanol. 0.87 g of saturated aqueous ammonia was added, followed by thorough stirring. The methanol was allowed to evaporate to collect crystals, which were then washed with acetone and analyzed.

EXAMPLE 3

2 g of 1,5′-bitetrazole was measured out into a 50-ml beaker, and dissolved by addition of 50 ml of methanol. 10 ml of water and 1.37 g of benzylamine were added in this order. Crystals formed were collected and washed in the same manner as in Example 2, dried and analyzed.

EXAMPLE 4

1,5′-bitetrazole were obtained using amines other than those used in Examples 1, 2 and 3 and following the procedure of Example 1, 2 or 3.

EXAMPLE 5

The 1,5′-bitetrazole obtained in Examples 1 to 4 were subjected to determination of melting point and decomposition temperature, elementary analysis, infrared absorption analysis, and NMR analysis. The results are shown in Tables 1 to 8.

In the column of “decomposition” in Tables 1 and 2, “sharp” indicates that the decomposition occurred in a narrow temperature range, while “broad” indicates that the decomposition occurred over a broad temperature range.

TABLE 1

Melting Point and Decomposition Temperature

Primary Amine Salt

De-

comp.

Boiling Point/

M.P.

Temp.

Sublimation Temp.

Decom-

Amine salt

(° C.)

(° C.)

(° C.)

position

1,5-BHT.H

2

O

—

148

sharp

Ammonium

—

185

sharp

Monomethylamine

159

170

sharp

Ethylamine

123

176

broad

n-Propylamine

—

206

sharp

Isopropylamine

—

218

258

broad

sec-Butylamine

168

197

broad

t-Butylamine

145

187

broad

n-Hexylamine

—

181

sharp

n-Octylamine

93

185

broad

2-Ethylhexylamine

85

185

broad

Oleylamine

91

188

broad

Allylamine

—

209

sharp

Cyclohexylamine

159

189

broad

Monoethanolamine

125

169

sharp

Aniline

132

206

broad

Benzylamine

135

185

broad

Phenethylamine

155

186

broad

Guanidine

187

189

sharp

Aminoguanidine

174

177

sharp

Dicyandiamide

—

201

sharp

3-Amino-1H-

—

167

sharp

1,2,4-triazole

Ethylenediamine

—

185

sharp

Hexamethylenediamine

141

172

sharp

m-Phenylenediamine

—

201

233

broad

m-Xylylenediamine

166

186

broad

Hydrazine

144

178

broad

1-Urea

131

149

217

broad

2-Urea

119

151

215

broad

Thiocarbohydrazide

141

194

sharp

Melamine 1/3

190

255

311

broad

Melamine 2/3

189

251

305

broad

Melamine 1/1

—

256

326

broad

Notes:

(1) In Tables 1 and 2, “—” indicates that no clear melting point was found by the determination.

(2) “1,5-BHT” indicates 1,5′-bitetrazole. The same applies hereinafter.

TABLE 2

Melting Point and Decomposition Temperature

Secondary and Tertiary Amine Salts

De-

comp.

Boiling Point/

M.P.

Temp.

Sublimation Temp.

Decom-

Amine salt

(° C.)

(° C.)

(° C.)

position

Dimethylamine

134

152

broad

Piperazine

—

205

sharp

Piperidine

—

183

broad

Diphenylamine

140

157

broad

Trimethylamine

—

204

sharp

Hexamethylene-

148

178

broad

tetramine

TABLE 3

Elementary Analysis

Primary Amine Salt

C

H

N

Cal-

Cal-

Cal-

Amine Salt

cd.

Found

cd.

Found

cd.

Found

1,5-BHT.H

2

O

15.39

15.42

2.58

2.52

71.78

71.25

t-Butylamine

34.12

35.57

6.20

6.24

59.68

58.63

n-Hexylamine

44.16

33.21

7.16

5.89

52.68

59.86

n-Octylamine

44.93

43.53

7.92

7.74

47.15

49.84

2-Ethylhexylamine

44.93

44.59

7.92

8.07

47.15

47.50

Oleylamine

59.23

58.88

9.69

10.12

31.08

30.64

Allylamine

30.77

29.53

4.65

4.59

64.58

63.66

Cyclohexylamine

40.50

40.81

6.37

6.48

53.13

52.39

Monoethanolamine

24.12

24.60

4.55

4.60

63.29

62.00

Aniline

41.56

41.80

3.92

4.01

54.52

54.29

Benzylamine

44.08

44.92

4.52

4.51

51.40

51.81

Phenethylamine

46.33

46.38

5.05

5.20

48.62

48.00

Guanidine

18.28

19.07

3.58

3.43

78.15

78.63

Arninoguanidine

16.98

16.75

3.80

4.11

79.22

79.77

Dicyandiamide

21.62

21.58

2.72

3.00

75.65

74.21

3-Amino-1H-

23.08

22.80

2.91

2.88

74.01

74.23

1,2,4-triazole

Ethylenediamine

21.43

20.90

3.60

4.05

74.96

75.02

Hexamethylene-

37.79

36.21

7.13

7.08

55.08

55.32

diamine

m-Phenylenediamine

39.02

38.68

4.09

3.81

56.88

57.01

m-Xylylenediamine

34.95

34.56

3.91

4.05

61.14

59.48

Hydrazine

15.59

15.39

2.62

2.43

81.80

82.56

1-Urea

18.19

17.85

3.05

2.93

70.69

70.76

2-Urea

18.61

18.78

3.90

3.87

65.10

66.17

Thiocarbohydrazide

15.71

15.38

2.64

3.09

73.27

71.68

Melamine 1/3

20.00

20.00

2.44

2.50

77.76

78.00

Melamine 2/3

20.90

20.17

2.51

2.60

76.60

75.80

Melamine 1/1

22.73

22.61

3.05

2.98

74.22

73.99

TABLE 4

Elementary Analysis

Secondary and Tertiary Amine Salts

C

H

N

Cal-

Cal-

Cal-

Amine Salt

cd.

Found

cd.

Found

cd.

Found

Dimethylamine

26.23

25.37

4.95

4.50

68.82

69.07

Piperazine

26.52

26.51

3.89

4.11

69.58

68.27

Piperidine

37.66

37.43

5.87

5.97

56.47

55.97

Diphenylamine

54.72

55.85

4.26

4.11

41.02

41.57

Trimethylamine

30.45

30.17

5.62

5.49

63.92

63.15

Hexamethylene-

34.53

34.14

5.07

5.11

54.83

59.01

tetramine

TABLE 5

Infrared Spectroscopic Analysis

Primary Amine Salt

Amine Salt

Characteristic Absorption (cm

−1

)

Ammonium

νNH2856.5

Monomethyl-

(N—CH3) νasCH 2879.5, νaCH 2758.0

amine

(N—CH3) δasCH 1461.9. δsCH 1380.0

(—NH3+) δasNH 1544.9. δsNH 1494.7

Ethylamine

(—CH3) νasCH 2999.1. (CH2) νasCH2 2912.3,

νsCH2 2912.3

(—CH3) δasCH 1463.9, δsCH 1377.5

(—NH3+) δasNH 1571.9, δsNH 1491.6

n-Propylamine

(—CH3) νasCH 2977.9, (CH2) νasCH2 2906.7,

νsCH2 2846.9

(—CH3) δasCH 1460.0, δsCH 1380.6

(—NH3+) δasNH 1606.6, δsNH 1514.4

Isopropylamine

(—CH3) νasCH 2977.9, (CH2) νasCH2 2906.7,

νsCH2 2846.9

(—CH3) δasCH 1460.0, δsCH 1380.6

(—NH3+) δasNH 1589.2, δsNH 1514.4

sec-Butylamine

(—CH3) νasCH 2977.9, (—CH3) δasCH 1460.0,

δsCH 1387.6

(—CH—(CH3) 2) skeleton 1187.6

(—NH3+) δasNH 1589.2, δsNH 1514.4

t-Butylamine

(—CH3) νasCH 2970.2. νsCH 2883.4

(—C—(CH3) 3) skeleton 1262.0, 1218.9, 964.1

n-Hexylamine

(—CH3) νasCH 3002.4, (GH2) νasCH2 2979.8,

νsCH2 2860.2

(—CH3) δasCH 1458.1, δsCH 1370.8,

—CH2—rocking 708.1

(—NH3+) δasNH 1610.0, δsNH 1513.2

n-Octylamine

(—CH3) νasCH 2954:5, νsCH2 2856.4,

(CH2) νasCH2 2918.1

νasCH2 2823.6, (—CH3) δasCH 1461.9, δsCH 1376.8

(—NH3+) δasNH 1604.7, δsNH 1500.5

2-Ethylhexyl-

(—CH3) νasCH2962.5, νsCH2 2871.8,

(CH2) νasCH2 2931.6

amine

νasCH2 2856.4, (—CH3) δasCH 1461.9, δsCH 1373.2

(—NH3+) δasNH 1618.4, δsNH 1508.2

Oleylamine

(—CH3) νasCH 2952. 2, (CH2) νasCH2 2918. l,

νsCH2 2850. 6

(CH3) δasCH 1463.9, δsCH 1372.1,

—CH2—C═C—1435.4

(—NH3+) δasNH 1606.6, δsNH 1506.3

Allylamine

(—C═CH) νCH 3023.9, (CH2) νasCH2 2919.8,

νsCH2 2837.3

(—C═C—) νC═C 16.07.7, δ in plane

CH 1441.4, δ out of plane CH 863.6

Cyclohexyl-

(CH2) νasCH2 2935.5, νsCH2 2862.2

amine

(—CH2) δCH scissors 1454.2

(—NH3+) δasNH 1591.2, δsNH 1488.0

Monoethanol-

(CH2) νasCH2 2933.5, νsCH2 2879.5

amine

(—CH2) δCH, scissors 1479.3

(—NH3+) δasNH 156.4, δsNH 1502.4

Aniline

νCH 3047.8˜2574.8, δ out of plane

CH 1967.7, 1831.3, 1751.0 1647.1

(—NH3+) δasNH 1596.8, δsNH 1498.6

Benzylamine

(—CH2—) δ scissors CH 1456.2

(—NH3+) δasNH 1575.0, δsNH 1495.2

(—CH2—) νasCH 2929.7, νout of plane

CH 1955.7, 18380.4, 1750.0

Phenethyl-

(—CH2—) δ scissors CH 1460.0

amine

(—NH3+) δasNH 1583.7, δsNH 1496.7

Guanidine

νNH 3435.0˜3361.7

νC═N 1654.8

Aminoguanidine

νNH 3448.5˜3260.7

νC═N 1674.1, (—NH3+) δasNH 1544.9,

δsNH 1453.3

Dicyandiamide

νNH 3438.8—3260.7, νC═N 2193.8, 2167.5

νC═N 1689.5, 1641.3

3-Amino-1H-

νNH 3369.4˜3265.3, νC═N 1679.9, 1647.1

1,2,4-triazole

(—NH3+) δasNH 1556.4, δsNH 1505.9

Ethylenediamine

νNH 3456.2˜3074.3.(—NH3+) δasNH 1624.4

(—NH2—) νasCH 2943.4, νsCH 2883.4,

scissors CH 1455.7

Hexamethylene-

νNH 3433.0˜3026.3, (—NH3+) δasNH

1556.4, δsNH 15U5.9

diamine

(—CH2—) νasCH 2935.4, νsCH 2868.0,

δ scissors CH 1463.9

m-Phenylene-

νNH 3476.1˜3080.1, (—NH3+) δasNH

diamine

1596.8.δsNH 1498.6

νCH 3047.8˜2574.8, δ out of plane

CH 1967.7, 1831.3, 1751.0, 1647.1

m-Xylylene-

νCH 3448.5˜3023.9, (—NH3+) δasNH

diamine

1595.7, δsNH 1504.4

(overlapped with Ph nucleus) δCH out of plane 1649.0

(—CH2—) νasCH 2918.9, νCH 2894.7,

δ scissors CH 1479.3

Hydrazine

νNH 3325.0˜3055.0

(—NH3+) δasNH 1610.5, δsNH 1519.8

Urea

νNH 3419.6˜3095.5, (—NH3+) δasNH

1593.1, δsNH 1505.9

νC═O non—association 1697.2,

νC═O association 1652.9

Thiocarbo-

νNH 3211.3, (—N3+) δasNH 1527.5,

δsNH 15U5.9

hydrazide

νC═O non—association 1625.9

δC═S 1527.5, 1279.9, 1120.6, 931.6, 767.9

Melamine 1/3

νNH 3461.7˜3328.9, (—NH2)

δ in-plane scissors NH 1668.3, 1552.6

(—NH3+) δasNH 1614.3, δsNH 1504.4

(—NH2) δ out-of-plane scissors NH 1094.5, 812.2

Melamine 2/3

νNH 3461.7˜3334.7, (—NH2) δ in-plane

scissors NH 1670.2, 1554.5

(—NH3+) δasNH 1612.4, δsNH 1506.3 (—NH2)

δ out-of-plane scissors NH

1095.5, 812.2

Melamine 1/3

νNH 3469.7˜3332.8, (—NH2) δ in-plane

scissors NH 1664.5, 1552.6

(—NH3+) δasNH 1614.3, δsNH 1500.0

(—NH2) δ out-of-plane scissors NH 1022.7, 813.9

TABLE 6

Infrared Spectroscopic Analysis

Secondary and Tertiary Amine Salts

Amine Salt

Characteristic absorption (cm

−1

)

Dimethylamine

(—CH3) νasCH 2976.0, νsCH 2759.9, δasCH 1460.0,

δsCH 1382.8

νCH 3406.7˜3026.1, (—NH3+) δasNH 1544.9,

δsNH 1494.7

Piperazine

(—CH2) νasCH2 2950.9, νsCH2 2862.2,

δsNH scissors 1460.0

NH 3236.8, 2758.0, δNH1608.9

Piperidine

(—CH2) νasCH2 2950.9, νsCH2 2862.2,

δCH scissors 1428.2

νNH 2753.6, 2526.3, 1607.7

Diphenylamine

νNH 3419.6, (—NH3+) δasNH

1610.5, δsNH 1519.R

νCH 3091.7, δ out of plane

CH 1697.2, 1652.9, Ph nucleus 1593.1

Trimethylamine

(—CH2) νasCH 3004.9, νsCH2 2756.1,

δasNH 1460.0,

δsCH 1384.0

νNH 3398.3˜3246.8, (—NH+)

δasNH 1544.9, δsNH 1494.7

Hexamethylene-

νC—N 1238.1, δCH2 rocking 1008.7, 817.8, 657.7

tetramine

TABLE 7

NMR Analysis

Primary Amine Salt

Amine Salt

(ppm)

Solvent

Ammonium

δ9.95 (s, 1H)

D

2

O

Monomethylamine

δ9.7 (s, 1H), δ2.75 (S, 3H)

D

2

O

Ethylamine

δ9.7 (s, 1H), δ3.35-2.95 (q, 2H),

D

2

O

δ1.5-1.25 (t, 3H)

n-Propylamine

δ9.0 (s, 1H) δ2.5-2.1 (t, 2H)

D

2

O

δ1.4-0.8 (2H), δ0.6-0.3(t, 3H)

Isopropylamine

δ9.1 (s, 1H), δ1.0 (d, 6H).6 3.5-3.0 (1H)

D

2

O

n-Butylamine

δ9.9 (s, 1H), δ3.3 (9H)

DMSO

sec-Butylamine

δ9.9 (s, 1H), δ1.5(t, 2H), δ1.1(d, 6H),

DMSO

δ3.3 (1H)

t-Butylamine

δ9.7 (s, 1H), δ1.4 (s, 9H)

D

2

O

n-Hexylamine

δ9.9(s, 1H), δ1.5 (13H)

DMSO

n-Octylamine

δ9.7 (s, 1H), δ2.0-2.1 (n, 14H),

D

2

O

δ0.8 (s, 3H)

2-Ethylhexyl-

δ9.7 (s, 1H), δ2.9-3.1 (d, 2H)

D

2

O

amine

δ1.5-1.0 (m, 6H), δ0.8-1.0(m, 6H)

Oleylamine

δ9.7 (s, 1H), δ5.2 (s, 2H), 1.0 (s, 28H).

DMSO

δ0.7 (s, 3H)

Allylamine

δ9.9 (s, 1H), δ5.3 (t, 2H), δ5.8(1H),

DMSO

δ3.4 (d, 2H)

Cyclohexylamine

δ9.7 (s, 1H), δ3.4-3.0 (1H),

D

2

O

δ2.2-1.0 (10H)

Monoethanol-

δ9.0 (s, 1H), δ3.3-3.0 (t, 2H),

D

2

O

amine

δ2.7-2.4 (t, 12H)

Aniline

δ9.2 (s, 1H), δ6.9 (s, 5H)

D

2

O

Benzylamine

δ9.9 (s, 1H), δ7.4 (ph, 5H), δ4.1 (s, 2H)

DMSO

Phenethylamine

δ9.65 (s, 1H), δ7.25 (s, 5H),

D

2

O

δ3.5-2.8 (dd, 4H)

Guanidine

δ9.9 (s, 1H), δ6.9 (s, 1H),

D

2

O

δ3.35 (s, 2H)

Aminoguanidine

Hydrogen in amine cannot be

DMSO

independently determined

Dicyandiamide

δ9.9 (s, 1H)

DMSO

3-Amino-1H-

δ8.1 (s, 1H)

D

2

O

1,2,4-triazole

Ethylenediamine

δ9.7 (s, 2H), δ3.6 (s, 4H)

D

2

O

Hexamethylene-

δ9.7 (s, 2H), δ3.3-2.8 (4H),

D

2

O

diamine

δ2.1-1.3 (4H)

m-Phenylene-

δ9.7 (s, 2H), δ7.6-7.2 (4H)

D

2

O

diamine

m-Xylylenediamine

δ9.9 (s, 2H), δ7.5 (ph, 4H), δ4.1 (s, 4H)

DMSO

Hydrazine

δ9.7 (s, 2H),

D

2

O

1-Urea

δ10.1 (s, 1H), δ7.5 (s, 5H)

DMSO

2-Urea

δ10.2 (s, 1H), δ8.2 (s, 6H)

DMSO

Thiocarbohydrazide

δ9.8 (s, 2H)

D

2

O

Melamine 1/3

δ9.8 (s, 3H), δ6.5 (s, 10H)

DMSO

Melamine 2/3

δ7.3 (s, 2H), δ4.6 (s, 8H)

DMSO

Melamine 1/1

δ8.0 (s, 1H), δ3.4 (s, 4H)

DMSO

TABLE 8

NMR Analysis

Secondary and Tertiary Amine Salts

Amine Salt

(ppm)

Solvent

Dimethylamine

δ9.7 (S, 1H), δ2.4 (s, 6H)

D

2

O

Piperazine

δ9.7 (s, 1H), δ3.85 (s, 8H)

D

2

O

Piperidine

δ9.7 (s, 1H), δ3.4-3.0 (t, 4H),

D

2

O

δ2.0-1.6 (s, 6H)

Diphenylamine

δ10.0 (s, 1H), δ7.2 (t, 4H)

DMSO

δ7.1 (d, 4H), δ6.8 (t, 2H)

Trimethylamine

δ9.9 (s, 1H), δ2.8 (s, 9H)

DMSO

Hexamethylene-

δ9.7 (s, 1H), δ4.7 (s, 12H)

D

2

O

tetramine

The above results reveal that the 1,5′-bitetrazole of the invention is a novel substance.

EXAMPLE 6

The crystals of 1,5′-bitetrazole piperazine salt obtained in Example 1 were finely ground in a mortar, added to a low-density polyethylene (melting point: 90° C.) in a proportion of 5 wt. % relative to the polyethylene, and extrusion-molded using an extruder at a resin temperature of 140° C., giving master chips having a diameter of about 3 mm and a length of about 3 mm.

EXAMPLE 7

The crystals of 1,5′-bitetrazole guanidine salt obtained in Example 4 were finely ground in a mortar, added to an acrylonitrile-styrene resin (AS resin; Vicat softening point: 104° C.) in a proportion of 5 wt. % relative to the resin, and extrusion-molded using an extruder at a resin temperature of 140° C., giving master chips having a diameter of about 3 mm and a length of about 3 mm.

EXAMPLE 8

The master chips obtained in Example 6 were added to a polypropylene resin to be molded, in a proportion of 2 wt. % relative to the resin, and injection-molded at 220° C. using a test mold measuring 3 mm thick, 100 mm wide and 100 mm long and having ribs with three different widths of 4 mm, 5 mm and 6 mm. The obtained molded article was compared with a blank molded article containing no foaming agent. The blank article had sinkmarks on the surface opposite to the ribbed surface and was commercially unacceptable, whereas the molded article containing the foaming agent of the present invention was completely free from sinkmarks.

EXAMPLE 9

The master chips obtained in Example 7 were added to a polyacetal resin to be molded, in a proportion of 2 wt. % relative to the resin, and injection-molded at 210° C. using a test mold measuring 3 mm thick, 100 mm wide and 100 mm long and having ribs with three different widths of 4 mm, 5 mm and 6 mm. The obtained molded article was compared with a blank molded article containing no foaming agent. The blank article had sinkmarks on the surface opposite to the ribbed surface and was commercially unacceptable, whereas the molded article containing the foaming agent of the present invention was completely free from sinkmarks and had a smooth skin layer.

COMPARATIVE EXAMPLE 1

Master chips were prepared in the same manner as in Example 6 except for using 20 wt. % of ADCA in place of the crystals of 1,5′-bitetrazole piperazine salt, and added to a polypropylene resin to be molded, in a proportion of 2 wt. % relative to the resin. The mixture was injection-molded at 220° C. using a test mold measuring 3 mm thick, 100 mm wide and 100 mm long and having ribs with three different widths of 4 mm, 5 mm and 6 mm. The obtained molded article was compared with a blank molded article containing no foaming agent and with the molded article of Example 8. The molded article obtained in this comparative example was satisfactorily foamed but had so-called “silver blisters”, i.e., air bubbles on the surface. Also, the mold was severely contaminated when repeated test molding was carried out.

COMPARATIVE EXAMPLE 2

Master chips were prepared in the same manner as in Example 7 except for using 20 wt. % of ADCA in place of the crystals of 1,5′-bitetrazole guanidine salt, and added to a polyacetal resin to be molded, in a proportion of 2 wt. % relative to the resin. The mixture was injection-molded in the same manner as in Comparative Example 1. The obtained molded article was compared with a blank molded article and with the molded article of Example 9. The molded article obtained in this comparative example was satisfactorily foamed but had so-called “silver blisters”, i.e., air bubbles on the surface, and did not have clearly defined edges. Also, the mold was severely contaminated when repeated test molding was carried out.

Number	Name	Date
5439251	Onishi et al.	Aug 1995
5682014	Highsmith et al.	Oct 1997
5872329	Burns et al.	Feb 1999

Substituted ammonium salt of 1,5′-bitetrazole

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CPC

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US Referenced Citations (3)

Foreign Referenced Citations (1)

Substituted ammonium salt of 1,5&#x02032;-bitetrazole

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

US Classifications

Field of Search

US

International Classifications

Abstract

Description

Claims

US Referenced Citations (3)

Foreign Referenced Citations (1)

Substituted ammonium salt of 1,5′-bitetrazole