COMPOSITES News
Hemp gets the green light The numerous potential applications for industrial hemp match the nearly utopian dream of the composites industry that is on the look out for stronger yet cheaper materials, with a lower carbon footprint, says Angelica Buan in this report. Potential, but outlawed The cannabis plant, commonly known as marijuana, is a strictly regulated plant that is classified as a narcotic and one that has been receiving attention lately due to its potential to cure cancer. Aside from its medicinal properties, the weed, also known as Cannabis Sativa L, possesses ideal properties for a wide variety of industrial applications. While marijuana is of the Cannabis Indica variety, the hemp used as industrial composite material is Cannabis Sativa, a non-psychoactive variety.
Industrial hemp farming is sustainable and requires no chemicals, pesticides or herbicides
Nevertheless, industrial hemp has suffered the blow of being akin to its psychoactive substance-containing twin, marijuana. The cultivation of what would have been a nostrum material to drive market value for major industries has been politically curbed. For instance, the 1937 Marijuana Tax Act implemented in the US almost maimed the potential of industrial hemp, believed to be useful for nearly 50,000 variety of products ranging from building composites and cellophane to automotive parts. But recent developments have pushed several states in the US to legalise industrial hemp farming and research. Countries like China, the UK and Canada (the latter has legalised industrial hemp production since 1992) continue to grow industrial hemp, while elsewhere, cultivating all varieties of cannabis is outlawed. The origin of hemp can be traced back to Central/South Asia and its cultivation for fibre goes back to ancient China. Hemp is defined as containing less than 0.3%
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of the intoxicating substance Tetrahydrocannabinoids (THCs), compared to marijuana’s THC range of 10% to 30%. Hemp farming is sustainable, as growing hemp requires no chemicals, pesticides or herbicides. In fact, hemp adds on and conditions the soil where it grows, while as a cash crop, hemp is grown in rotation with other crops. Getting high on hemp Industrial hemp as a material for the plastics industry has been known since the early 20th century, when hempderived cellulose was promoted as an affordable and renewable raw material. Of all natural fibres, hemp merits as being the strongest and most durable. Hence, hemp-reinforced plastics are found to be up to ten times stronger than petroleumbased plastics, as well as 100% biodegradable. Today, it is seeing its use in a variety of industries. In 2014, Canadian company Hempearth commissioned a Florida-based aircraft manufacturer to build the world’s first hemp fibre-based plane. Currently crowdfunding for an initial working capital of US$500,000, the company has designed a four-seater, two-engine aircraft with a cruising speed a little over 340 km/hour. It also has a wingspan of 12 m that will be constructed from at least 75% hemp, including the wings, seats, pillows, and outer shell. The colour of the plane will be that of natural hemp fibre and the plan is for it to run completely on hemp biofuel, derived from the seed of the weed.
The world's first hemp plane will take off in North Carolina in 2016
Using hemp as a biofuel could improve carbon efficiency, too, citing research done by Professor Richard Parnas at the University of Connecticut. He found that hemp converts to biodiesel at a 97% efficiency rate and can burn at lower temperatures than any other biodiesel available on the market.