Manufacturing plastics from Tapioca starch .
Previously, cassava is the main application in the food industry as noodles , pasta , bread , and other confectionery products . Starch is known to be an indispensable ingredient in the food industry . However, there are still many other applications from starch . Some typical applications such as starch is used to make adhesives and fillers in the paper industry and cardboard boxes , adhesive fibers in the garment industry , as the dispenser for capsules ( antibiotics ) and promote physical disintegration in water with compressed tablets ( Decolgen ) .... With the constant advancement of science and technology , many applications achievements starch realize this may not have been discovered and used . We've heard of cars running on fuel made from cassava starch ( gasohol ) , super-absorbent gel from starch , even plastics ( plastics ) made from starch .
For many people , the starch into plastic imagination is seemingly impossible , so the process of how this happens ?
Abstract
Study on starch to produce biodegradable plastics began in the 1970s . At first, these studies do not attract attention to understand , but later due to environmental issues , climate change and limited resources of raw materials the world have flocked to research new materials to replace the previous traditional materials . To promote the research process , both technological innovations and aggressive marketing plan being promoted . Thus consciousness has created for people, especially consumers when they purchase new materials acceptable replacement for traditional materials while the new material has a much higher price . Biodegradable plastic is a new material developed for use as the traditional plastic but has the molecular structure can be destroyed by the activities of the enzymes secreted by the bacteria in the environment available the wild .
If these materials are decomposed in a suitable environment such as plants decompose , they can decompose into CO2 , water and microbial substances without causing any toxic agent to the environment round . Although biodegradable plastic can be produced from petroleum sources , but most of the research focused on the biological material to prevent depletion issues in future materials and make the environment around the cleaner. In all biological materials , the starch is promising to offer the best possible future for very large quantities and low cost as well as the ability of its biodegradable in the environment .
Production of biodegradable plastics from starch .
2 starch granules contain sugar polymers exist as semi-crystalline . Granule structure is quite stable , and can decompose at temperatures 2200C ( Shogren , 1993 ) . The approach of the ability of starch in the production of biodegradable plastics will be conducted in the following ways :
1 . Starch is a biodegradable resin fillers .
Starch granules can be mixed directly with the polymer melt temperature - high pressure in the grain structure remains unchanged , so that the starch granules will stick in the polymer chain (Figure 1 ) . In this way , the amount of starch was mixed in plastic polymer molecules ; applications in film industry : 10 % starch adhesive films on a ( plastic ) ( Griffin , 1994) .
Initially , the starch granules binder with plastic , however the ability to mix depending on the type of starch structure is used in the mixture. Because the structure of starch and plastic are two different types of hydrogen ( hydrophilic and hydrophobic ) , so we can not link together easily , so the adhesive will create a heterogeneous mixture of plastic . To overcome this problem , the starch must first be converted ( with chemicals ) into hydrophobic . Hydrophobic modified starch can be mixed with the resin in mixing footage . One more note , in the film industry of film thickness can not be thinner than the size of the starch granules , so there are still certain limitations .
2 . TPS material ( Thermoplastic Starch ) or thermoplastic materials
TPS material is plastic polymer can change the form of soft or melt under high temperature - high pressure or hard when frozen form . Most plastics are present in the form of TPS , so they can be made into films , containers or anything that has a definite shape . In nature , starch is not thermoplastic materials , semi-crystalline molecules in starch granules are automatically converted into the molecular organization of higher forming stable crystalline structure . As a result , the melting temperature of starch is higher than its decomposition temperature , therefore , the decomposition process will take place before the melting process if we baked starch . However, thanks to the participation of the additive , the crystalline structure of starch granules can be broken and starch grain can melt at very low temperatures and creating new material called thermoplastic materials or TPS . When baked , thermoplastic member ( TPS ) will be melted and can be made to any desired objects thanks to combined machinery appropriate tools to participate in processes such as plastic filler machine , machine molding , film blowing machine ....
02Vat TPS material ( Thermoplastic Starch ) or thermoplastic materials
TPS material is plastic polymer can change the form of soft or melt under high temperature - high pressure or hard when frozen form . Most plastics are present in the form of TPS , so they can be made into films , containers or anything that has a definite shape . In nature , starch is not thermoplastic materials , semi-crystalline molecules in starch granules are automatically converted into the molecular organization of higher forming stable crystalline structure . As a result , the melting temperature of starch is higher than its decomposition temperature , therefore , the decomposition process will take place before the melting process if we baked starch . However, thanks to the participation of the additive , the crystalline structure of starch granules can be broken and starch grain can melt at very low temperatures and creating new material called thermoplastic materials or TPS . When baked , thermoplastic member ( TPS ) will be melted and can be made to any desired objects thanks to combined machinery appropriate tools to participate in processes such as plastic filler machine , machine molding , film blowing machine ....
Although water plasticized starch effects but irrelevant in making plastic products from TPS . When waterproof TPS will leave more brittle and cracked . Glycerol is commonly used plasticizer best TPS . Unlike starchy grains , TPS members can be used as the main component in the structure because plastic can melt TPS and created different shapes . However, TPS has two major drawbacks : it is very sensitive to water and low mobility . Most research in this area has focused overcome these two limitations . And the most common approach to improve the TPS is to change the structure of starch granules in the effects of chemicals ( starches ) and TPS into modified starch products will largely overcome the above disadvantages . The typical plant in the use of plastics from starch is Novamont ( Italy ) , Biotec ( Germany ) and Rodenburg (Netherlands ) ...
3 . Porous starch .
Conventional porous - porous polystyrene foam used for manufacturing ( materials to fill the excess space around the product in the box ) , foam shelf and other porous materials . To become biodegradable material , the foam manufacturing process uses only the starch water during blowing to create holes in the sponge structure . Porous starch waterproof and has many outstanding characteristics than polystyrene foam . Ham fabricated using porous starch with other polymers such as polyvinyl alcohol , polycaprolactone and polyactic acids are usually ways to improve the properties of starch foam .
03en Manufacturing plastics from starch .
Porous starch (Figure 3 ) is one of the first biodegradable products are warmly consumers and accounting support market stability in many years . As reported by the Messias de Braganca and Flower Market , the U.S. alone has 25 % polystyrene foam has been replaced by foam made from starch ( 2004), while the UK has 20 % market share is porous starch foam . This percentage is increasing steadily because of the quality of starch foam increasingly improved . The company main produce starch that is ECO Foam - FOAM of National Starch and Chemical ( USA ) , Green Cell Foam of KTM Industries, Inc. . ( USA ) and EcoFlo of Green Light Product Ltd ( UK ) .
4 . Application of lactic acid from starch in the fermentation process .
As a pure sugar polymer capable of re-use , starch is used as a raw material for the manufacture of industrial products such as alcohols , aldehydes , esters and acid for a long time . In this product , lactic acid is attracting a lot of attention in the role of basic materials to help successfully develop biodegradable plastics . Lactic acid is a substance used for producing polylactic acid ( PLA ) a product has many potential applications in industrial production . In the last decade , a lot of scientific research in theory and practice to promote the development of polylactic acid is a polymer properties of this substance . A perfect process to produce PLA has formed and manufacturing the world's largest NatureWorks PLA (USD ) LLC starch solution to produce PLA . PLA is a biodegradable plastic has many features similar to traditional plastic , it is used more familiar products such as vegetable bags , disposable food bags , film containers , toys , appliances family and some car decorations . With the development of technology , the PLA is an important material in the replacement of non-biodegradable materials in the future . This promises PLA demand will increase and the demand for production materials - starch will also increase.
