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Two microporous fabrics, one formed by lamination and the second by coating, along with a nylon woven fabric, were subjected to a simulated sea spray environment.The water vapor transmission rates of the treated fabrics and of treated controls were determined using the desiccant method. As expected, in all cases, the rate of moisture vapor transmission for the treated samples was significantly lower than that for the untreated. The majority of the blockage was inherent in the base fabric, with smaller amounts attributable to the microporous substrates.Clothing is used to control the exchange of thermal energy by resisting evaporative transfer and by resisting thermal transfer [4]. In the case of typical waterproof clothing, protecting the wearer from penetration from exterior moisture has often just as effectively prevented excess interior moisture generated by metabolic processes from escaping. This creates an imbalance between the body's energy production and its exchange of energy with the environment, leading to the wearer's discomfort. As an example, the metabolic moisture production of an average person walking at a speed of 5.5 km/hour has been calculated [I] ] to be approximately 54 g/M2/h. A silicone rubber coated nylon ' fabric typically used for rainwear has a water vapor transmission rate (WVTR) [4] of 6.3 g/M2/h. A significant improvement in comfort of waterproof garments has been achieved through the development of waterproof or breathable fabrics termed &dquo;microporous fabrics.&dquo; Basically, these fabrics are constructed to allow moisture vapor to pass through relatively easily while acting as a barrier to liquid water. At present, there are three commercially viable methods of producing microporous fabrics: (a) laminating a microporous membrane (film) to a base fabric, (b) applying a microporous coating to a base fabric, and (c) constructing super-high density woven fabrics using ultra-fine yarns.In general, microporous fabrics, despite their premium price and some early problems, have met with wide consumer acceptance, especially in functional garments such as parkas, running suits, and rainwear. Studies (see Mooney [2], for example) suggest that no single advertised property of these fabrics is responsible for their purchase, but rather, when aggregated, the functional properties often predominate as the reason for their selection.Prior to 1978, microporous fabrics had been susceptible to contamination by body oils, insect repellents [3], suntan oils, and surfactants found in laundry detergents [5]. These problems were solved by modified versions of the fabrics; however, blockage of the pores, by whatever means, seems to be a hazard ' around which one cannot easily engineer, and therefore its consequences must be considered. We are interested in the performance of microporous fabrics in a particularly demanding environment, that of long-term exposure at sea where salt spray may remain on the fabric for a period of time. ExperimentalFor this study, we obtained two different commercially avai...

As part of the preparation for the Bartolomeo platform, various locations of the trunnion scuff plate were required. Scuff plate MLI blankets were removed and recovered from Columbus ISS in August 2019 as part of these EVA activities. These blankets having seen more than 11 years in orbit are extremely valuable from a materials-science perspective where direct analysis of the impact of the space environment can be seen and evaluated to see its effect on materials, contamination and functionality of the blankets.

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