Study of silicon treatment of polyamide textiles for airbags

63 s. :il., tab., grafy +CD ROMThe key initial drivers to developing the airbags were performance (safety) and cost/benefit. As one can imagine, the key function of the airbag cushion is to absorb the impact. Nylon 6.6 has the most superior capability in energy absorption. The balance between the strength and elongation gives it unmatched suitability for airbag cushion materials. The performance attributes that have led to industry standardisation and use of over 60MM kilograms annually on this material are its breaking strength or tenacity; energy absorption capability or toughness; heat resistance; and stability over time as measured by accelerated ageing tests. Also with silicone coating, again, measured by accelerated ageing tests. However, more recently, a different selection criterion has started to come to the fore, that of proven performance or confidence. Since the airbag system forms part of the automotive supply chain there is continuous and necessary consideration of other materials such as polyester, for use in the airbag cushion. It is possible to demonstrate that all these alternatives, including polyester are significantly inferior to nylon 6.6 when measured against the key performance attributes, and that their use would pose a risk of failure in airbag applications. That lesser performance of polyester coupled with increasing legislative and litigation activity around automotive safety, and the lack of a track record in the global market for polyester have led to the conclusion that polyester is not appropriate for airbag cushion use for comparison purpose, the key physical properties of Nylon 6.6 and polyester are shown in table 6(a). The key differences between the two polymers are density and specific heat capacity