Biodegradable Polymers

In the recent years, bio-based and biodegradable products have raised great interest since sustainable development policies tend to expand with the decreasing reserve of fossil fuel and the growing concern for the environment. Bio-Polymers are a form of polymers derived from plant sources such as sweet potatoes, soya bean oil, sugarcane, hemp oil, and corn starch. These polymers are naturally degraded by the action of microorganisms such as bacteria, fungi and algae. Bio-plastics can help alleviate the energy crisis as well as reduce the dependence on fossil fuels of our society. They have some remarkable properties which make it suitable for different applications. This paper tries to give an insight about Bio-plastics, their composition, preparation, properties, special cases, advantages disadvantages, commercial viability, its life cycle, marketing and pricing of these products.
As a result, the market of these environmentally friendly materials is in rapid expansion,
10 –20 % per year.

1. BIODEGRADABLE POLYMERS HARCOURT BUTLER TECHNOLOGICAL INSTITUTE KANPUR DEPARTMENT OF PLASTIC TECHNOLOGY PRESENTED BY- SAURABH SUKLA SR. NO. – 470/13 3 RD B.TECH PLASTIC TECHNOLOGY

2. CONTENTS . Introduction. History. Uses of plastics in various fields. Application of plastics. Reasons of opposition of plastics. Biodegradable polymers. Biodegradation process. Types of biodegradable polymers. Application of Biodegradable Polymers. Importance of biodegradable polymers. Future aspects of biodegradable polymers. Conclusion. Reference.

3. HISTORY Biodegradable polymers have a long history and since many are natural products, the precise timeline of their discovery and use cannot be accurately traced. In 1980, One of the first medicinal uses of a biodegradable polymer “catgut suture” . The first catgut sutures were made from the intestines of sheep. Cellulose was discovered in 1838 by the French chemist Anselme Payee . In 1925 Polyhydroxybutyrate was first isolated and characterized by French microbiologist Maurice Lemoigne.

4. In the 1980s, Imperial Chemical Industries developed poly(3-hydroxybutyrate- 3-hydroxyvalerate) obtained via fermentation that was named “Biopol”. In 1992, an international meeting ,where leaders in biodegradable polymers met to discuss a definition, standard, and testing protocol for biodegradable polymers. [ Also, oversight organizations such as  American Society for Testing of Materials (ASTM) and the  International Standards Organization  (ISO) were created. As of 2013, 5-10% of the  plastic  market focused on biodegradable polymer derived plastics.

5. INTRODUCTION What actually biodegradable substance means ? Biodegradability means breaking down of large molecules into small molecules or decomposition , naturally by micro organism with in a short period of time (Few weeks or months). The substance that can be degraded by natural process termed as “BIODEGRADABLE” substance or those can not be degraded or take a very long period called “ NON BIODEGRADABLE” substance .

6. USES OF PLASTIC IN VARIOUS FIELDS Plastic production has increased from 0.5 to 260 million tones per yr since 1950. Every yr approx. 500 billions plastics bags are distributed but only 3% recycled . They are typically made of PE and can take up to 1000 yr to degrade in landfill.

7. APPLICATION OF PLASTICS CABLES BOTTLES PIPES TOYS

8. Plastics are used in almost every field such as - Packaging , furniture, medical, automobile industries, housing product, keyboard , mouse, bottles, files, cases & cover etc. So Plastics are used in daily life, but excess uses of plastics product has become very harmful for human life. Plastics faces many riots, protest, opposition. Always it is blamed that it is great threat of environment. Even in some countries plastics are banned and others are planning for same.

9. OUR OCEAN ARE TURNING INTO PLASTICS Plastics bags are chocking our oceans . An estimated every yr 50-80 millions end up in our environment . Once they enter in our precious water then they do not go away and remains for 1000 yr.

10. REASONS ?? NON BIODEGRADABLE Plastics eaten by animals is a big problem in today`s India. In U.N. report every yr approx. 1,00,000 animals die in all over world. Burning of plastic great threat of environment & also increases pollution in atmosphere.

11. How long until it`s gone?? PLASTIC CONTAINERS……………………... 50-80 YRS PLASTIC BOTTLES …………………………. 450 YRS RUBBER BOOT……………………………... 50-80 YRS FOAMED PLASTIC CUPS…………………… 50 YRS TINNED STEEL CANS……………………….. 50 YRS LEATHER SHOES……………………………. 25-40 YRS WOOL SOCKS……………………………... 1-5 YRS ALUMINIUM CANS…………………………. 200-500 YRS PLASTIC BAGS……………………………… 200-1000YRS DISPOSABLE DIAPERS………………………. 550 YRS CIGARETTE BUTTS…………………………... 10-12 YRS MILK COTTONS……………………………... 5 YRS

12. SOLUTION BIODEGRADABLE POLYMERS The term “BIODEGRADABLE” materials is used to describe those materials which can be degraded by the enzymatic action of living organism, such as bacteria, yeasts, fungi and the ultimate end products of the degradation process, these being CO2, H 2 O and biomass under aerobic conditions.

13. Characteristics of Biodegradable Polymers Inert Permeability Non- toxicity Bio-compatibility Tensile strength Mechanical strength Controlled rate of degradation

14. The long polymer molecules are reduced to shorter and shorter lengths and Undergo oxidation (oxygen groups attach themselves to the polymer molecules) This process is trigged by Heat, UV light, Mechanical stress etc. Oxidation causes the molecules to become hydrophilic (water attracting) and Small enough to be ingestible by micro-organism, setting the stage for biodegradation to begin. BIODEGRADATION PROCESS STEP- 1 ST

15. STEP 3 RD As micro- organism consume the degraded plastic, carbon dioxide, water and biomass are produced and returned to nature by way of the biocycle. STEP 2 ND Biodegradation occurs in the presence of moisture and micro-organisms typically found in environment. The plastic material is completely broken down in to the residual products of the biodegradation process .

16. SOURCES OF BIODEGRADABLE POLYMER Polysaccharides Starches Wheat Potatoes Maize Cassava Lingo- cellulose product Wood Straws Others Pectin Chitosan /chitin Gums

17. Polysaccharides It is polymeric carbohydrate molecules composed of long chains of monosaccharide units bound together by glycosidic linkages and on hydrolysis give the constituent monosaccharide's or oligosaccharides. They range in structure from linear to highly branched. Examples include storage polysaccharides such as starch and glycogen, and structural polysaccharides such as cellulose and chitin.

18. Chitosan Chitosan is a linear polysaccharide composed of randomly distributed β-(1-4)-linked D-glucosamine (deacetylated unit) and N-acetyl-D glucosamine (acetylated unit). It is made by treating shrimp and other crustacean shells with the alkali sodium hydroxide. Chitin is the second most abundant agro-polymer produced in nature after cellulose. Chitosan has a number of commercial and possible biomedical uses. It can be used in agriculture as a seed treatment and biopesticide, In industry, it can be used in a self-healing polyurethane paint coating. In medicine, it may be useful in bandages to reduce bleeding and as an antibacterial agent.

19. Biodegradable polymers are divided into three main categories Polyglycolic acid Polylactic acid Polycaprolactone Polyvinyl alcohol 1. Biodegradable polymers obtained by chemical synthesis--

20. 2.Biodegradable polymers produced through fermentation by microorganism- Polyesters Neutral polysaccharides 3. Biodegradable polymers from chemically modified natural product- Starch Cellulose Chitin and Chitosan Soy based plastic

21. Poly 3-hydroxyalkanoate PHA is one of the most common types of biodegradable plastics that can be found. PHA is made naturally when bacteria ferment lipids or sugars. The main advantage is that this type of bioplastics is very versatile, and its properties can be manipulated to create materials that are used in many different area. The medical industry currently is one of the biggest consumers of PHA bio plastics. PHA- Production of PHA- Produced under condition of Excess carbon Low limiting nutrient (P,S,N,O) Two different types: Short chain length. Medium chain length.

22. SYNTHESIS Microorganism which is used in synthesis of PHA is Alcaligenes eutrophus. PHA Polymer obtained is 80% of dry bacteria weight. Imperial chemical industries developed poly (3-hydroxy butyrate co 3- hydroxy valerate ) obtained via fermentation that was named “BIOPOL”

23. Recovery of PHA from cells After synthesis is the most imp step is the removal of polymer from bacteria so techniques which are cost efficient are used. PHA producing cells from found mainly in Nile River . Polymer is separated from cells using centrifugation and filtration. PHA is recovered using solvents like chloroform. Polymer is then purified.

24. Polylactic acid PLA plastics are called Polylactic acid plastics, usually fully transparent. This plastics is derived from certain forms of sugar cane and commonly used in packaging material, due to case of molding it almost any desired shape.

25. SYNTHESIS The starch is first hydrolyzed into glucose and then fermented into sodium lactate and by purification, obtained Lactic acid. This lactic acid forms a ring. This ring opens to combine and form polylactide. This polymer is then obtained and purified.

26. PLA CARBON CYCLE

27. Chemical and Physical Properties Due to the chiral nature of lactic acid, several distinct forms of polylactide exist: poly-L-lactide ( PLLA) is the product resulting from polymerization of L,L-lactide (also known as L-lactide). PLLA has a crystallinity of around 37% Glass transition temperature 60–65 °C. Melting temperature 173–178 °C Tensile modulus 2.7–16GPa. Heat-resistant PLA can withstand temperatures of 110 °C. PLA is soluble in chlorinated solvents, hot benzene , tetrahydrofuran, and dioxane.

28. Application of PLA polymer- Tea bags made from PLA. PLA cups used in restaurants. 3D Printed Human skull with data from Computed Tomography.Transparent PLA

29. Future of PLA

30. IMPORTANCE OF BIODEGRADABLE POLYMER Improper disposal and failure to recycle results in overflowing landfills. 100% Biodegradable. Produced from renewable resources. Able to RECYCLED, BURNED without producing toxic products. Localized delivery of drugs. Reduce side effects. Controllable degradation rate

31. FUTURE OUTLOOK OF BIODEGRADABLE POLYMERS Development of biodegradable polymers for consumer and property requirements for many applications in which biodegradability would be an important materials property is a major challenge. Biodegradable Polymers Challenges that need to be addressed in the coming years include management of raw materials, performance of biodegradable materials, and their cost for production. Economy of scale will be one of the main challenges for production of Biodegradable polymers. It is very important to develop- New manufacturing routes by replacing existing methods with high yields New microbiological strains/enzymes Efficient downstream processing methods Biodegradable polymers products. Many developments are currently underway to develop various polyamides, polyesters , Polyhydroxyaloknates , etc. with a high differentiation in their final properties for use in automotive, electronics, and biomedical applications.

32. Biodegradable polymers are closer to the reality of replacing conventional polymers than ever before. Nowadays , biodegradable polymers are commonly found in many applications from commodity to hi-tech applications due to advancement in biotechnologies and public awareness. However , despite these advancements, there are still some drawbacks which prevent the wider commercialization of bio-based polymers in many applications. This is mainly due to performance and price when compared with their conventional counterparts, which remains a significant challenge for bio-based polymers. CONCLUSION

33. REFERENCE https://en.wikipedia.org/wiki/Biodegradable_polymer . https://en.wikipedia.org/wiki/Polylactic_acid Bastioli,editor,Catia(2005). Handbook of biodegradable polymers. Shawbury, Shrewsbury, Shropshire, U.K.: Rapra Technology .  ISBN   9781847350442 . Plastics- The Facts 2012"  (PDF). Plastics Europe. Retrieved 9 February 2014. New emerging trends in synthetic biodegradable polymers – Polylactide: A critique. European Polymer Journal 2007 43 4053-4074 PLA MSDS. ampolymer.com