PPC - Propylene Carbonate |
The poly (propylene carbonate) (PPC) is a sustainable polymer undergoes a complete incineration ashes without accompanied f ormation of CO2 and H2O. The poly (propylene carbonate) (PPC) is a biodegradable aliphatic polyester which is synthesized from the copolymerization of carbon dioxide (CO2) and propylene oxide (PO).
The terpolymerization of PO and EO with CO2 can be performed using zinc glutarate catalyst. The resulting products are ternary copolymers, containing units greater than 80% carbonate. About $ 1.85 / kg, PO is a product of relatively high value because you present catalysts are very expensive. Carbon dioxide (CO2 ) is currently considered as a mass air pollutant causing the greenhouse effect. From an economic and ecological view it is advantageous to use carbon dioxide as a monomer to produce useful material.
However, copolymers of propylene oxide and carbon dioxide, poly (propylene carbonate) (PPC), showed some degradability. The copolymer of ethylene oxide and carbon dioxide, poly (ethylene carbonate) (PEC), exhibits a better biodegradability than the copolymer of propylene oxide and carbon dioxide, poly (propylene carbonate) (PPC).
In the human body the PEC disappears completely after 2 weeks without apparent ill effect. Biodegradation rate of pellets made from blends PPC and decreases with increasing PEC content PPC. The glass transition temperature and the decomposition temperature of the PEC is much lower than that of the CFP and shows a similar property to rubber.
Propylene glycol glycerol derivative of a biodiesel plant, it may be advantageous over the use of PO in the production of PC and PPP.
Two other polycarbonates found some commercial applications are polyethylene carbonate (PEC) and poly (cyclohexene carbonate).
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Symbols
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- Propylene Carbonate
- Poli(propylene carbonate)PPC
- Carbonato de propileno
- C4H6O3
- Poli (carbonato de propileno)
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Properties PPC |
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Good mechanical properties for packaging applications.- Product safely degradation (water and CO2).
- biocompatible
- Compatible with fillers and other polymers.
- Thermal properties suitable for processing.
- high transparency
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Thermal properties PPC
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However, the PPC still has significant shortcomings, as its low decomposition temperature and low glass transition temperature (Tg), which severely limit their thermal temperature. Stability and practical application as a viable biodegradable plastic. The PPC has a melting point of -55 ° C (-67 ° F) boiling point of 240 ° C (-464 ° F), flash point of 132 ° C and autoignition temperature of 455 ° C.
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Physical properties PPC
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The PPC is amorphous at room temperature. The glass transition temperature is 38 ° C, the thermal degradation temperature is 252 ° C and the density is 1.27 g / cm3 at 25 ° C, 1.9 GPa Young modulus and tensile strength of 29 MPa. A small amount (1 wt%) of nano-sheets of graphene oxide (GO) can significantly strengthen the PPC.
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Electrical properties PPC
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Good dielectric in high - energy cells and capacitors, c omo an aprotic solvent and plasticizer for polymers and in removing CO2 and H2S from natural gas and petroleum cracking. Because of its high dielectric constant of 64, it is often used as electrolyte component high - capacity lithium batteries, generally together with a low viscosity solvent.
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Optical properties PPC
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Competes in terms of applications with other plastics such as polipropilene (PP) or polystyrene (PS), PLA is quite transparent, has high gloss and low haze. The optical properties of PLA are sensitive to the additives added and processing effects. Films and rigid containers are thermoformed high volume applications .
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Chemical properties PPC
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PPC is soluble in polar solvents p. acetone, methyl ethyl ketone, ethyl acetate, dichloroethane, while it is insoluble in ethyl alcohol, glycols, water and aliphatic hydrocarbons. Inhibition of chain scission was demonstrated by using additives of citric acid with low residue after the decomposition of the polymer matrix.
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Processability PCC |
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The PPC can be processed is similar to the polyolefins (extrusion, injection molding and thermoforming) | |
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Polimerization PPC |
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There is not much information available for PPC synthesis from CO2 and propylene glycol. In fact, propylene glycol is used in the manufacture of PO which, in turn, becomes PC and PPP.
The poly (propylene carbonate) (PPC) of propylene oxide (PO) and CO2 is mediated by the complex zinc glutarate and chromium.
The properties and composition of the polymer are substantially affected by copolymerization conditions, ie temperature, pressure, solvent and the initial concentration of reagents.
PPC linkage with a percentage of 93% molar carbonate with zinc glutarate in toluene at 80 ° C and a pressure of 4.5 MPa CO2. |
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Alloys PPC |
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Polycarbonate diols aliphatic (PCD) can be used as chain extenders for elastomers such as thermoplastic urethanes. When copolymerized with isocitantes, improve flexibility, toughness and adhesive strength. They also provide excellent chemical and hydrolytic stability and thermal resistance and abrasion. In general, they are more expensive than polyether diols and polyester, but have superior aging properties. Therefore, this class of polyols is mainly used for polyurethane elastomers of high performance operating in hostile environments. Aliphatic polycarbonates may also be used as curing agents in thermosetting resins, as binders in ceramic compositions sacrifice and biodegradable plastics and mixtures of PPC / starch.
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Applications PPC |
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The polymer is attractive because it is made by the f ixing CO2, biodegradable and biocompatibile. The PPC may have potential applications in industry as binder resins, thermoplastic polymers substitutes (eg, polyethylene and polystyrene) and hydrolytically and / or biodegradable polymers. Compounds of PPC and starch can be used as biodegradable plastics. PPC also used in applications where the required oxygen diffusion through the structure.
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