Architectural membrane material is generally made up of a base cloth and coating. The fabric cloth of high strength polyester fiber or glass fiber is woven through a certain way to provide tensile or tearing strength of membrane materials. The coating and surface layer provide protection to the base cloth, which can improve the durability and self-cleaning performance of membrane material.
Under high stress state, the higher the tensile strength of membrane material is, the less creep fatigue and aging will occur. During the production and construction process, any scratches or folding crease will affect the strength of membrane materials. Therefore, the membrane material in the membrane structure must have higher tensile strength and tearing strength.
As a permanent or semi-permanent building, the membrane material itself must fully meet the relevant requirements of the fireproof index of the building materials. In Japan, for example, membrane structure have been successfully applied to the many large public buildings back in 1980s, and the membrane material of glass fiber cloth coated with PTFE (PTFE materials),has already passed the national fire test, although not been included as non-combustible materials in national building standards, for each single building membrane material must pass the fire test, and met all requirements. It is generally considered that PTFE material is non-combustible material, and PVC material is flame retardant material.
The durability of the membrane material is not only related to the nature of the base cloth itself, different kinds of coating provide different degree of protection to the base, also affects the service life of the membrane material. Generally speaking, the warranty period of PTFE material is more than 25 years, and the warranty period of PVC material is 10 years ~15 years. So far, some PTFE material buildings is still in use for over 35 years, and some PVC material buildings has been served over 20 years, and still in normal usage.
Self-cleaning is the antifouling and self-cleaning ability of the membrane material itself. Cause the UV chemical instability of PVC material, especially in summer, PVC coating is easy to segregate and become sticky and dust adhesion, which is not easy to be washed away by the rain, not only unsightly, also reducing the use of life. Therefore, generally, when PVC membrane material is used in buildings, an additive layer of PVF (polyvinyl fluoride) or PVDF (Polyvinylidene two fluoroethylene) or organ-silicone is used outside the PVC coating to effectively improve the self-cleaning performance of the PVC membrane material. The PTFE film material has good antifouling and self-cleaning performance itself and does not need any additive surface coating.
If the membrane structure is located in the urban area or bustling downtown, the sound insulation performance of the building is higher. Single layer membrane structures are often used in places where sound insulation is not too high, or they usually use ingenious design and construction methods to improve the sound insulation performance.
The thermal insulation performance of single layer material is roughly equivalent to the laminated glass, if a building has higher requirements on thermal insulation performance, have to consider the double layer or multi-layer structure, but it also damages the transmission performance of the building. In order to achieve the harmonization of the above contradictions, a specific method must be sought for a specific building, such as using an inner membrane material with better light transmittance.