| abstract |
Methods for making a pressed monolithic gas generant for an inflatable restraint device (for example, an airbag system for a vehicle) are provided. The methods include admixing a gas generant material with a ballistic performance modifier to form a mixture. The mixture is granulated. Then, a pressed monolithic gas generant grain is formed by applying pressure to the granulated mixture, where the grain has an actual density of at least about 95% of the maximum theoretical density. The pressure may be applied in a controlled manner to both side of the gas generant material in a die cavity, and removing formed grain from die cavity while maintaining some pressure to both sides of the grain, thereby further improving various pyrotechnic properties. The methods of the disclosure provide pyrotechnic compositions that are economical to manufacture, have improved burn rate, combustion profile, effluent quality, strength, durability, and integrity of the grain, while having a consistent shape between different production lots. |