Additives: is a substance which is added generally is small concentration to resins in order in to alter their properties either for failiate processing or to change the physical, chemical, electrical, properties of end product. Additives change the properties of plastic, help the meet the recycling requirements, most plastics contain other organic or inorganic compounds blended in. The amount of additives ranges from zero percentage for polymers used to wrap foods to more than 50% for certain electronic applications. The average content of additives is 20% by weight of the polymer. Filers improve performance and/or reduce production costs. Stabilizing additives include fire retardants to lower the flammability of the material.
The term additives are used in the plastics industry may applied to any substance that is added generally in small concentration to resins in order to alter their properties either facilitate processing or to change the physical, chemical, electrical properties of end products.
Physical additives: to modify plastic properties means, plasticizes, lubricants, impact modifiers, fillers, pigments’.
Chemical additives: achieve their effect by chemical reaction, heat stabilizers, antioxidants, Uv absorbers, Flammable retardants.
Condenzation: molecular weight of polymer is less to the weight of monomer, by product is not formed, reaction is formed. X+x=1½x+½x
Need for Additives:
Additives Can:
1. Change the properties of plastic materials
2. Enlarge the field of application drastically
3. Protect your plastic against alteration and degradation
4. Help to meet the recycling requirements o 5. 5. Extend the lifetime of product
6. Differentiate with others.
Features of Additives:
1. Should be efficient in their function.
2. Should be stable under processing and service conditions.
3. Should not bleed or bloom.
4. Should be non-toxic and should not impart taste or odour.
5. Should not adversely affect the properties of the polymers.
6. Should be cheap.
Plastic Additives:
Segments Focused on Plastics Additives:
Segments Focused on Plastics Additives:
Plastics Industry
Without Additives No Plastic
New Application because of Additives
Value Generation by Recyclo additives
Additives which assist processing
Additives are classified according to their specific function rather than on a chemical basis:
Processing Stabilizers: The resistance of polymer to thermal degradation
Lubricant (External and Internal): Frictional behavior of melt on the metal surface.
Processing Aid and Flow Promotors: Melting viscosity of the polymer.
Thixotropic Agents: Processing variables
Additives which modify bulk properties
1. Plasticizer
2. Reinforcing Fillers
3. Toughening Agents
Additives used to reduce formulation cost
1. Fillers
2. Diluents and extenders
Additives for surface modification
1. Anti-static agents
2. Slip additives
3. Adhesion promoters
4. Anti wear additives
Additives used for optical modifier
1. Nucleating agents
2. Colorants
Additives for anti aging properties
1. UV Absorber
2. Fungicides
Additives used for others
1. Blowing agents
2. Flame retardant
3. Bio or photo degradable
4. Foaming agents
Case Study I: Additive for chain extender
Case Study I: Additive for chain extender
Chain Extension Chemistry
Advantages of chain extender additives
Case Study I: Additive for chain extender
Case Study I: Chain Extender for PET Film (Performance)
Case Study II: Additive for Flow Promoters
Flow Mechanism
1. Increase melt strength (betterprocessing ability, better bubble stability, prevent breaking, higher processing speed, low warping)
2. Increase IV (intrinsic viscosity), decrease MFR
3. Increase mechanical properties (tensile and impact strength), not as dramatic as impact modifier.
4. Compatibilisation alloy is possible (PLA blend,PA-PET, etc.)
5. Replace/Reduce SSP (Solid state polymerization) time for pet.
6. Maintaining transparency
Flow modifier
1. Increase MFR
2. Reduce cycle time
3. Improve dispersion (ADD), higher loading is possible.
4. Maintaning transparency.
5. High thermal stabilty.
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