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‘Unsinkable’ boat has foam centre
applications
Nanofibres pass conductivity tests
The carbon nanofibres allow a current to pass through the structure and light up a 75 W lightbulb.
A CONDUCTIVE glass reinforced plastic (GRP) ‘bridge’ has been developed by engineering students from Dayton, Ohio, USA. The ‘Hot-span’ bridge is actually a small test structure 61 cm (24 inches) long by 10 cm (4 inches) wide. It is made of GRP with conductive carbon nanofibres incorporated into the glass reinforced epoxy resin road surface (which the students called the ‘NANO-Sphalt’). The main bridge structure is pultruded with some glass composite reinforcement applied by hand to the side via a wet lay-up process. The road surface was produced via a hand lay-up process. The students, who are from the University of Dayton Research Institute (UDRI), say that they wanted to test the conductive properties of carbon nanofibres enclosed in a nonconductive material when subjected to mechanical stress. If successful, the tests could demonstrate the potential of using nanomaterials for a variety of functions in fibre reinforced plastic (FRP) structures. The bridge was tested to initial stages of mechanical failure in a three-point bending test while a 110 V alternating
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REINFORCEDplastics
current was applied to the ends of the structure in order to light up a 75 W light bulb. The students found that the light bulb remained illuminated throughout the test. The current was also applied to raise the temperature of the bridge surface. During 20 minutes, the surface temperature, monitored with thermocouples, rose slowly to 40°C and was warm to the touch. According to UDRI, a new process was used to disperse the carbon nanofibres (obtained from Applied Science Inc of Cedarville, Ohio) in the epoxy resin. This allowed the nanofibres to be uniformly dispersed in the resin to create a suitably conductive road surface. The nanoparticle dispersion process used was developed by UDRI and researchers at WrightPatterson Air Force Base. UDRI is currently scaling up the process to 5-23 kg (10-50 lb) batch sizes and the nanomaterials produced are commercially available from Nanosperse LLC of Akron, Ohio, the exclusive licensee of the technology. The bridge was submitted to the Society for the Advancement of Material and Process Engineering (SAMPE) seventh annual Super Lightweight Composite Bridge Building Contest at Long Beach, California, USA. The goal of this contest is to build a lightweight bridge structure that maximises the ratio of bending strength to bridge weight. Dr Don Klosterman; University of Dayton Research Institute; e-mail: Donald.Klosterman@udri. udayton.edu; website: www.udri. udayton.edu.
July/August 2004
‘Unsinkable’ boat has foam centre A BOAT BUILDER based in Chennai, India, claims to have made an unsinkable houseboat made of glass fibre composite. Vadyar Boats Pvt Ltd says that using polyurethane foam in the manufacture of its fibre reinforced plastic (FRP) houseboat makes the vessel impossible to sink, even when filled with water. The houseboat is designed for Jungle Lodge and Resorts Ltd, which provides entertainment for tourists in Bangalore. The company intends to use the boat to transport tourists in the Kabini Reservoir, which is part of the Rajiv Gandhi National Park, a major tourist destination. The £12 000 boat is 10 m long and 6 m wide with a 0.7 m thickness and can carry a maximum of 40 people, with a full loaded weight of approximately 10 tons. It is designed as a twin hull catamaran comprising two interconnected pontoons and a deck and is fitted with a 25 horsepower mariner outboard motor. FRP makes up the majority of the structure, and was chosen for its lightweight and non-corrosive qualities. The shell of the boat is moulded from fire retardant isophthalic resin and several layers of glass fibre chopped strand mat and woven rovings. The inside walls are made of thick, waterresistant plywood coated with FRP and the deck is coated with three additional layers of FRP. The room structures are made of corrugated FRP and the roof is also covered with corrugated glass fibre composite sheets. The surface of all the glass fibre
The houseboat, designed for the tourist industry, is claimed to be unsinkable.
composite partitions and roofs are sprayed with fire resistant paint. The entire boat was fabricated in easily portable units and transported by road for about 400 km. It was then assembled on site and launched onto the lake. The polyurethane foam was foamed in situ from polyurethane combined with equal measures of isocyanide and polyol. According to Vadyar, once the foam had been inserted, the boats were tested for buoyancy by filling both pontoons with water and loading them with deck, roof, all steel structures, total number of passengers, outfits and outboard motor. Even when filled or overflowing with water, the pontoons had around 20 cm of free board available. Vadyar also makes lifeboats, fast rescue boats and high speed passenger launches and has supplied over 400 boats for the Indian Navy, the coastguard, and for shipyards and ship owners. Vadyar has built two rescue boats for the Indian Navy made with a double skin canopy filled with polyurethane foam, whihc is said to give the boats a selfrighting property. P.A. Ramakrishnan, Vadyar Boats Pvt Ltd; e-mail: [email protected].
Nanofibres pass conductivity tests
The carbon nanofibres allow a current to pass through the structure and light up a 75 W lightbulb.
A CONDUCTIVE glass reinforced plastic (GRP) ‘bridge’ has been developed by engineering students from Dayton, Ohio, USA. The ‘Hot-span’ bridge is actually a small test structure 61 cm (24 inches) long by 10 cm (4 inches) wide. It is made of GRP with conductive carbon nanofibres incorporated into the glass reinforced epoxy resin road surface (which the students called the ‘NANO-Sphalt’). The main bridge structure is pultruded with some glass composite reinforcement applied by hand to the side via a wet lay-up process. The road surface was produced via a hand lay-up process. The students, who are from the University of Dayton Research Institute (UDRI), say that they wanted to test the conductive properties of carbon nanofibres enclosed in a nonconductive material when subjected to mechanical stress. If successful, the tests could demonstrate the potential of using nanomaterials for a variety of functions in fibre reinforced plastic (FRP) structures. The bridge was tested to initial stages of mechanical failure in a three-point bending test while a 110 V alternating
8
REINFORCEDplastics
current was applied to the ends of the structure in order to light up a 75 W light bulb. The students found that the light bulb remained illuminated throughout the test. The current was also applied to raise the temperature of the bridge surface. During 20 minutes, the surface temperature, monitored with thermocouples, rose slowly to 40°C and was warm to the touch. According to UDRI, a new process was used to disperse the carbon nanofibres (obtained from Applied Science Inc of Cedarville, Ohio) in the epoxy resin. This allowed the nanofibres to be uniformly dispersed in the resin to create a suitably conductive road surface. The nanoparticle dispersion process used was developed by UDRI and researchers at WrightPatterson Air Force Base. UDRI is currently scaling up the process to 5-23 kg (10-50 lb) batch sizes and the nanomaterials produced are commercially available from Nanosperse LLC of Akron, Ohio, the exclusive licensee of the technology. The bridge was submitted to the Society for the Advancement of Material and Process Engineering (SAMPE) seventh annual Super Lightweight Composite Bridge Building Contest at Long Beach, California, USA. The goal of this contest is to build a lightweight bridge structure that maximises the ratio of bending strength to bridge weight. Dr Don Klosterman; University of Dayton Research Institute; e-mail: Donald.Klosterman@udri. udayton.edu; website: www.udri. udayton.edu.
July/August 2004
‘Unsinkable’ boat has foam centre A BOAT BUILDER based in Chennai, India, claims to have made an unsinkable houseboat made of glass fibre composite. Vadyar Boats Pvt Ltd says that using polyurethane foam in the manufacture of its fibre reinforced plastic (FRP) houseboat makes the vessel impossible to sink, even when filled with water. The houseboat is designed for Jungle Lodge and Resorts Ltd, which provides entertainment for tourists in Bangalore. The company intends to use the boat to transport tourists in the Kabini Reservoir, which is part of the Rajiv Gandhi National Park, a major tourist destination. The £12 000 boat is 10 m long and 6 m wide with a 0.7 m thickness and can carry a maximum of 40 people, with a full loaded weight of approximately 10 tons. It is designed as a twin hull catamaran comprising two interconnected pontoons and a deck and is fitted with a 25 horsepower mariner outboard motor. FRP makes up the majority of the structure, and was chosen for its lightweight and non-corrosive qualities. The shell of the boat is moulded from fire retardant isophthalic resin and several layers of glass fibre chopped strand mat and woven rovings. The inside walls are made of thick, waterresistant plywood coated with FRP and the deck is coated with three additional layers of FRP. The room structures are made of corrugated FRP and the roof is also covered with corrugated glass fibre composite sheets. The surface of all the glass fibre
The houseboat, designed for the tourist industry, is claimed to be unsinkable.
composite partitions and roofs are sprayed with fire resistant paint. The entire boat was fabricated in easily portable units and transported by road for about 400 km. It was then assembled on site and launched onto the lake. The polyurethane foam was foamed in situ from polyurethane combined with equal measures of isocyanide and polyol. According to Vadyar, once the foam had been inserted, the boats were tested for buoyancy by filling both pontoons with water and loading them with deck, roof, all steel structures, total number of passengers, outfits and outboard motor. Even when filled or overflowing with water, the pontoons had around 20 cm of free board available. Vadyar also makes lifeboats, fast rescue boats and high speed passenger launches and has supplied over 400 boats for the Indian Navy, the coastguard, and for shipyards and ship owners. Vadyar has built two rescue boats for the Indian Navy made with a double skin canopy filled with polyurethane foam, whihc is said to give the boats a selfrighting property. P.A. Ramakrishnan, Vadyar Boats Pvt Ltd; e-mail: [email protected].