Well for my chem assessment, I have to find current developments on a biopolymer (I chose to do PHB) and this information has to come from resources published in the last 3 years and I can't actually find any that recent. Can some link me some resources in that time frame please?
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PHB resources (1 Viewer)
- Thread starter unown971
- Start date
– Name of Biopolymer: Biopol™
§ It is made of polyhydroxybutyrate (PHB) and polyhydroxyvalerate (PHV).
– Organism Used:
§ Alcaligenes eutrophus (a bacterium).
– Production:
§ In industrial production, A. Eutrophus is grown in an environment favourable to its growth to create a very large population of bacteria (such as high nitrates, phosphates and other nutrients).
§ When a sufficiently large population has been produced, the environment is changed to one that is high in glucose, high in valeric acid and low in nitrogen.
§ This unnatural environment induces the production of the polymer by the bacterium; the polymer is actually a natural fat storage material, created by the A Eutrophus in adverse conditions.
§ Large amounts of a chlorinated hydrocarbon, such as trichloromethane are added to the bacteria/polymer mix; this dissolves the polymer.
§ The mixture is then filtered to remove the bacteria.
§ The polymer is extracted from the hydrocarbon solvent as a powder, which is then melted or treated further to create a usable polymer.
– Properties:
§ It is BIODEGRADABLE and BIOCOMPATIBLE
§ It is non-toxic, insoluble in water, permeable to oxygen, resistant to UV light, acids and bases, high melting point, high tensile strength
– Uses in Relation to Properties:
§ It has many medical applications (e.g. biocompatible stiches that dissolve or are absorbed by the body)
§ Disposable containers for shampoo, cosmetics, milk bottles, etc., as it only takes 2 years to decompose back into natural components
§ Disposable razors, cutlery, rubbish bags, plastic plates, etc.
– Advantages:
§ It is biodegradable, unlike polyethylene and other petroleum derived plastics, and so will help to reduce levels of rubbish in land fills
§ It is compatible with organisms (biocompatible); it is not rejected by the body’s immune system and so can be used safely
§ It is a renewable resource
– Disadvantages:
§ It is currently very expensive, and currently the demand is not high enough for it to be economically viable
– Future Developments:
§ Recently, the gene for producing Biopol polymer strands from the Alcaligenes Eutrophus bacteria was extracted and implanted into E. coli using genetic engineering techniques. E. coli bacteria are much easier to grow than other bacteria, and thus are cheaper
§ Nutrient sources are starting to be derived from waste materials, such as molasses and other agricultural wastes. This greatly reduces costs.
· Biopolymer: a naturally occurring polymer produced by living organisms, including plants, animals and microorganisms
o Biopolymers are biodegradable, biocompatible and renewable
Pg 14-19:
Poly(3-hydroxybutyrate)
· Bacteria ‘Alcaligenes eutrophus’ are grown in fermentation vats with high conc. glucose, lowered conc. nitrogen, and 30⁰ temperature
· PHB produced up to 80% of bacteria’s dry weight.
· PH3B is extracted using solvents like halogenated hydrocarbons which break bacterial cell walls and separate plastic from cell debris.
· PHB is then milled to a powder/pellets
· Properties and uses
o Thermoplastic: can be melted, moulded, shaped into various forms
o Similar to polypropylene, but biodegradable, biocompatible and renewable
o Degrades slowly in the body, and is biocompatible/non-toxic
§ Potentially used as controlled drug-release carrier
§ Used in stitches/sutures
o Biodegradability is a disadvantage for many applications where the plastic must not break down over time
o Breaks down in anaerobic conditions of landfill
§ Disposable nappies, bottles, bags, packaging materials
o Good oxygen permeability
§ Use as wrapping film
o Similar physical properties to polypropylene: brittle, rigid, crystalline, high tensile strength, high MP
§ Brittle nature limits its use
o Copolymers, e.g. with 3-hydroxy pentanoate (to make BioPol), are more flexible, and hence have more applications and potential use in the future
o High production costs (5-7 x petrochemical plastics) limits its use currently
There you go mate, more than enough
§ It is made of polyhydroxybutyrate (PHB) and polyhydroxyvalerate (PHV).
– Organism Used:
§ Alcaligenes eutrophus (a bacterium).
– Production:
§ In industrial production, A. Eutrophus is grown in an environment favourable to its growth to create a very large population of bacteria (such as high nitrates, phosphates and other nutrients).
§ When a sufficiently large population has been produced, the environment is changed to one that is high in glucose, high in valeric acid and low in nitrogen.
§ This unnatural environment induces the production of the polymer by the bacterium; the polymer is actually a natural fat storage material, created by the A Eutrophus in adverse conditions.
§ Large amounts of a chlorinated hydrocarbon, such as trichloromethane are added to the bacteria/polymer mix; this dissolves the polymer.
§ The mixture is then filtered to remove the bacteria.
§ The polymer is extracted from the hydrocarbon solvent as a powder, which is then melted or treated further to create a usable polymer.
– Properties:
§ It is BIODEGRADABLE and BIOCOMPATIBLE
§ It is non-toxic, insoluble in water, permeable to oxygen, resistant to UV light, acids and bases, high melting point, high tensile strength
– Uses in Relation to Properties:
§ It has many medical applications (e.g. biocompatible stiches that dissolve or are absorbed by the body)
§ Disposable containers for shampoo, cosmetics, milk bottles, etc., as it only takes 2 years to decompose back into natural components
§ Disposable razors, cutlery, rubbish bags, plastic plates, etc.
– Advantages:
§ It is biodegradable, unlike polyethylene and other petroleum derived plastics, and so will help to reduce levels of rubbish in land fills
§ It is compatible with organisms (biocompatible); it is not rejected by the body’s immune system and so can be used safely
§ It is a renewable resource
– Disadvantages:
§ It is currently very expensive, and currently the demand is not high enough for it to be economically viable
– Future Developments:
§ Recently, the gene for producing Biopol polymer strands from the Alcaligenes Eutrophus bacteria was extracted and implanted into E. coli using genetic engineering techniques. E. coli bacteria are much easier to grow than other bacteria, and thus are cheaper
§ Nutrient sources are starting to be derived from waste materials, such as molasses and other agricultural wastes. This greatly reduces costs.
· Biopolymer: a naturally occurring polymer produced by living organisms, including plants, animals and microorganisms
o Biopolymers are biodegradable, biocompatible and renewable
Pg 14-19:
Poly(3-hydroxybutyrate)
· Bacteria ‘Alcaligenes eutrophus’ are grown in fermentation vats with high conc. glucose, lowered conc. nitrogen, and 30⁰ temperature
· PHB produced up to 80% of bacteria’s dry weight.
· PH3B is extracted using solvents like halogenated hydrocarbons which break bacterial cell walls and separate plastic from cell debris.
· PHB is then milled to a powder/pellets
· Properties and uses
o Thermoplastic: can be melted, moulded, shaped into various forms
o Similar to polypropylene, but biodegradable, biocompatible and renewable
o Degrades slowly in the body, and is biocompatible/non-toxic
§ Potentially used as controlled drug-release carrier
§ Used in stitches/sutures
o Biodegradability is a disadvantage for many applications where the plastic must not break down over time
o Breaks down in anaerobic conditions of landfill
§ Disposable nappies, bottles, bags, packaging materials
o Good oxygen permeability
§ Use as wrapping film
o Similar physical properties to polypropylene: brittle, rigid, crystalline, high tensile strength, high MP
§ Brittle nature limits its use
o Copolymers, e.g. with 3-hydroxy pentanoate (to make BioPol), are more flexible, and hence have more applications and potential use in the future
o High production costs (5-7 x petrochemical plastics) limits its use currently
There you go mate, more than enough