Kopcilova Michaela

Připojil(a) se dne 9. 4. 2019
Přidáno 2 775 bajtů ,  9. 4. 2019
2
(1)
 
(2)
Řádek 28: Řádek 28:


# <u>Recycling old blanks</u> – mixing collected polyurethane cuttings (60%) from old surfboards with virgin foam. Recycling method works only with EPS and does not work with PU. However, PU is preferred because it is more flex, more dense, stronger and cheaper. EPS has tendency to be dumped quicker. PU blanks cannot be recycled as easily as EPS because PU blank sucks the resin into it  (Woody, 2009).
# <u>Recycling old blanks</u> – mixing collected polyurethane cuttings (60%) from old surfboards with virgin foam. Recycling method works only with EPS and does not work with PU. However, PU is preferred because it is more flex, more dense, stronger and cheaper. EPS has tendency to be dumped quicker. PU blanks cannot be recycled as easily as EPS because PU blank sucks the resin into it  (Woody, 2009).
# <u>Plant based materials</u>  – in the past blanks made of sugar. However this is a difficult material. It rottens very quickly once the board is broken  
# <u>Plant based materials</u>  – in the past blanks made of sugar. However this is a difficult material. It rots very quickly once the board is broken.
# <u>Wood</u> has been used as a principal material in the surfboard construction since ancient Hawaiians started to shape wave-riding tools. However, wood is heavy and does not have same performance (Barcelos, Magnago, & Leripio, 2018).
# <u>Cork</u> is completely natural, recyclable and biodegradable, it does not absorb water and, therefore, it does not rot, it resists and absorbs impacts. However, it is expensive to build cork boards and it is hard to adapt to serial manufacturing (Mateus, Bordado, & dos Santos, 2017).
# <u>Mushrooms</u> – Eco friendly Mycelium material is a glue made from fungus roots, and binds plant-based materials – usually crop waste like plant stalks and seed husks. This agricultural waste and mushroom mycelium are put into a mould, where it grows into a shape of the board. It is very strong material which floats and repels water jus as effectively as the foam plastics. It is biodegradable, sustainable and 100% natural (Brodeur, Brunet, & Primiani, 2011; Vartiainen, 2018).
 
'''<u>Resin</u>'''
 
# <u>Bio-based resin</u> - pine sap and rapid-renewable plant oils (used in the bio fuel industry (‘Moss Research Announces “Industry-First” Sustainable Surfboards’, 2011).
# <u>Super Sap</u> made by Entropy Resin is made of byproducts of the pulp and paper industry and the biofuels industry, with total biological content varying between 25-50% depending on the specific resin used.  Research showed 50% reduction of CO2 emissions in Super  Sap resin compared to normal resins (Michelena, Graham-Jones, Summerscales, & Hall, 2016).
 
* Bio-based resin, however, cannot be 100% ecological because it is based on petrol. Surfboard constructors argue that bio-based resins are good but have also some disadvantages such as higher price, lower strength and not being as white as epoxy resins (Vartiainen, 2018).
 
'''<u>Natural fibers</u>'''
 
In normal surfboards, fiberglass is used. The overall CO2 footprint contribution of fiberglass is only 5%. Thus, alternatives to fiberglass are unlikely to result in any major environmental benefit through displacing fiberglass alone. However, alternatives to fiberglass exist: woven bamboo cloth, hemp cloth, and bamboo veneer. These alternatives have varying impacts on performance, durability, and visual appearance. It appears that bamboo would be the best. A bamboo plantation absorbs 5x more carbon dioxide and puts out 35% more oxygen than the equivalent plantation of trees. Bamboo is also one of nature’s most resistant fibers, and it is possible to weave these fibers together in such a way as to create a very active and responsive flex pattern in the surfboards. Bamboo fiber is also biodegradable and can be disposed of after the boards life is over (Vartiainen, 2018).
 
 
 
 


<br />
<br />