Gas generant compositions comprising melamine oxalate for use in automotive restraint devices
A gas generant composition for passive inflatable restraint systems (e.g., airbags) for automobiles is provided that comprises a melamine oxalate compound. The gas generant may be a cool burning gas generant composition that comprises a melamine oxalate compound, a co-fuel, such as guanidine nitrate, and an oxidizer, such as basic copper nitrate. The gas generant composition has advantageous combustion properties, including a maximum flame temperature at combustion (T c ) of ≤about 1700K (1,427° C.), a linear burn rate of ≥about 18 mm per second at a pressure of about 10 megapascals (MPa), a gas yield of the gas generant composition of ≥about 5.7 moles/100 cm 3 , and a linear burn rate pressure exponent of ≤about 0.35.
1 . A cool burning gas generant composition for an automotive inflatable restraint system comprising:
a melamine monoxalate compound having a molar ratio of melamine to oxalic acid of about 1:1;
guanidine nitrate; and
basic copper nitrate, wherein the gas generant composition has a maximum flame temperature at combustion (T c ) of less than or equal to about 1600K (1,327° C.), a linear burn rate of greater than or equal to about 18 mm per second at a pressure of about 10 megapascals (MPa), a gas yield of the gas generant of greater than or equal to about 5.7 moles/100 cm 3 , and a linear burn rate pressure exponent of less than or equal to about 0.35.
2 . A cool burning gas generant composition for an automotive inflatable restraint system comprising:
a dimelamine trioxalate compound, wherein the dimelamine trioxalate compound having a molar ratio of melamine to oxalic acid of about 2:3;
guanidine nitrate; and
basic copper nitrate, wherein the gas generant composition has a maximum flame temperature at combustion (T c ) of less than or equal to about 1520K (1,247° C.), a linear burn rate of greater than or equal to about 18 mm per second at a pressure of about 10 megapascals (MPa), a gas yield of the gas generant of greater than or equal to about 5.7 moles/100 cm 3 , and a linear burn rate pressure exponent of less than or equal to about 0.35.
3 . The cool burning gas generant composition of claim 1 having a maximum flame temperature at combustion (T c ) of greater than or equal to about 1400K (1,127° C.) to less than or equal to about 1600K (1,327° C.).
4 . The cool burning gas generant composition of claim 1 , wherein the melamine monoxalate compound is present at greater than or equal to about 5% by weight to less than or equal to about 30% by weight of the total gas generant composition.
5 . The cool burning gas generant composition of claim 1 , wherein the guanidine nitrate is present at greater than or equal to about 10% to less than or equal to about 50% by weight of the gas generant composition.
6 . The cool burning gas generant composition of claim 1 , wherein the basic copper nitrate is present at greater than or equal to about 30% to less than or equal to about 70% by weight of the gas generant composition.
7 . The cool burning gas generant composition of claim 1 , wherein the melamine monoxalate compound is present at greater than or equal to about 5% by weight to less than or equal to about 30% by weight of the total gas generant composition, the guanidine nitrate is present at greater than or equal to about 10% to less than or equal to about 50% by weight of the total gas generant composition; the basic copper nitrate is present at greater than or equal to about 30% to less than or equal to about 70% by weight of the total gas generant composition; and greater than or equal to 0% to less than or equal to about 10% by weight of the total gas generant composition of one or more gas generant additives.
8 . The cool burning gas generant composition of claim 2 , wherein the dimelamine trioxalate compound is present at greater than or equal to about 5% by weight to less than or equal to about 30% by weight of the total gas generant composition.
9 . The cool burning gas generant composition of claim 2 , wherein the guanidine nitrate is present at greater than or equal to about 10% to less than or equal to about 50% by weight of the gas generant composition.
10 . The cool burning gas generant composition of claim 2 , wherein the basic copper nitrate is present at greater than or equal to about 30% to less than or equal to about 70% by weight of the gas generant composition.
11 . The cool burning gas generant composition of claim 2 , wherein the dimelamine trioxalate compound is present at greater than or equal to about 5% by weight to less than or equal to about 30% by weight of the total gas generant composition, the guanidine nitrate is present at greater than or equal to about 10% to less than or equal to about 50% by weight of the total gas generant composition; the basic copper nitrate is present at greater than or equal to about 30% to less than or equal to about 70% by weight of the total gas generant composition; and greater than or equal to 0% to less than or equal to about 10% by weight of the total gas generant composition of one or more gas generant additives.