Polycarbonate
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This document discusses polycarbonate, including its history, chemical structure, synthesis, properties, and applications. Polycarbonate was developed in 1953 and introduced commercially in the 1960s. It is a thermoplastic polymer containing carbonate groups that is lightweight, transparent, and impact resistant. Polycarbonate is synthesized from bisphenol A and phosgene. It has various applications due to its properties, such as in bulletproof glass, eye lenses, bottles, and medical and automotive uses. However, it also has some disadvantages like scratching easily and high cost.
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Polymer engineering - Polycarbonate
slides contain some information about polycarbonate, as follow:
- History
- What is PC?
- Structure
- Production
- Processing
- Manufacturing & Block diagram
- Properties
- Applications
Polycarbonate
Polycarbonate is a thermoplastic polymer with carbonate groups in its chemical structure. It is a tough, clear plastic with high impact strength even at low temperatures. Polycarbonate is synthesized via the transesterification of bisphenol A and diphenyl carbonate or by the reaction of bisphenol A with phosgene. It has good mechanical properties, heat resistance, and transparency. Common applications of polycarbonate include bulletproof glass, eyeglasses, headlight lenses, and components in electrical and medical devices.
Polystyrene
Polystyrene is produced from styrene, which was first distilled from tree resin in 1839. It is prepared through the polymerization of styrene, which can be done through various techniques like solution polymerization. Polystyrene has good thermal insulation properties and is used in many applications like building insulation, food packaging, toys, and more. It is chemically inert but dissolves in some organic solvents and is flammable.
Polycarbonate
1. The document summarizes information about polycarbonate presented by the Smile Group to the Chemical Department faculty of engineering.
2. Polycarbonate is a thermoplastic polymer with strong, durable, and impact-resistant properties making it suitable for a variety of industrial and commercial applications.
3. The presentation covers the history, chemical structure, production process through condensation reaction, properties, classification, morphology, methods of production, mechanical strength and various applications of polycarbonate.
Polycarbonate
This document is a presentation by three students - AbdAl-Rhman Magdy AbdullahYoussef, AbdAl-Rhman Ali Basheer, and Amr Ahmed Saeed - on polycarbonate. It was supervised by Prof. Maher Gamal and Eng. MohammedYahiya. The presentation discusses the discovery and manufacturing of polycarbonate, its properties, applications in electronics, automotive, and construction, and safety considerations for handling and storage. It describes the interfacial polymerization process used to produce polycarbonate industrially using bisphenol A and phosgene, followed by separation, extrusion, pelletizing, drying and packaging steps. Major polycarbonate manufacturers include S
Polyethene
Polyethylene is the most common plastic. Its global production is ca. 80 million tones.
Chemical Formula: (C2H4)nH2
http://apps.kemi.se/flodessok/floden/kemamne_eng/polyeten_eng.htm
http://en.wikipedia.org/wiki/Polyethylene
http://www.answers.com/Q/What_are_advantages_and_disadvantages_of_polythene
Phenolic Resin & Adhesives
This document provides information on phenolic resin adhesives and epoxy adhesives. It discusses that phenolic resins are thermoset polymers produced from reactions of phenol or substituted phenols with formaldehyde. They are used for applications like bonded abrasives, coated abrasives, and friction elements. The document also describes the synthesis and applications of epoxy resins, which include their reaction with hardeners, modifiers, fillers to produce one component or two component adhesives. Examples of formulations for general purpose, quick cure, and one component epoxy adhesives are also provided.
Silicon rubber pankaj kumar das
Silicon rubber is an inorganic polymer composed of silicon and oxygen in its backbone. It is synthesized from dimethyldichlorosilane through hydrolysis and polycondensation reactions. Silicon rubber has excellent thermal stability, flexibility even at low temperatures, and resistance to chemicals and weathering. It is widely used in medical applications like tubing and implants due to its biocompatibility, as well as in mechanical applications for seals, gaskets and vibration damping.
Recommended
Polymer engineering - Polycarbonate
slides contain some information about polycarbonate, as follow:
- History
- What is PC?
- Structure
- Production
- Processing
- Manufacturing & Block diagram
- Properties
- Applications
Polycarbonate
Polycarbonate is a thermoplastic polymer with carbonate groups in its chemical structure. It is a tough, clear plastic with high impact strength even at low temperatures. Polycarbonate is synthesized via the transesterification of bisphenol A and diphenyl carbonate or by the reaction of bisphenol A with phosgene. It has good mechanical properties, heat resistance, and transparency. Common applications of polycarbonate include bulletproof glass, eyeglasses, headlight lenses, and components in electrical and medical devices.
Polystyrene
Polystyrene is produced from styrene, which was first distilled from tree resin in 1839. It is prepared through the polymerization of styrene, which can be done through various techniques like solution polymerization. Polystyrene has good thermal insulation properties and is used in many applications like building insulation, food packaging, toys, and more. It is chemically inert but dissolves in some organic solvents and is flammable.
Polycarbonate
1. The document summarizes information about polycarbonate presented by the Smile Group to the Chemical Department faculty of engineering.
2. Polycarbonate is a thermoplastic polymer with strong, durable, and impact-resistant properties making it suitable for a variety of industrial and commercial applications.
3. The presentation covers the history, chemical structure, production process through condensation reaction, properties, classification, morphology, methods of production, mechanical strength and various applications of polycarbonate.
Polycarbonate
This document is a presentation by three students - AbdAl-Rhman Magdy AbdullahYoussef, AbdAl-Rhman Ali Basheer, and Amr Ahmed Saeed - on polycarbonate. It was supervised by Prof. Maher Gamal and Eng. MohammedYahiya. The presentation discusses the discovery and manufacturing of polycarbonate, its properties, applications in electronics, automotive, and construction, and safety considerations for handling and storage. It describes the interfacial polymerization process used to produce polycarbonate industrially using bisphenol A and phosgene, followed by separation, extrusion, pelletizing, drying and packaging steps. Major polycarbonate manufacturers include S
Polyethene
Polyethylene is the most common plastic. Its global production is ca. 80 million tones.
Chemical Formula: (C2H4)nH2
http://apps.kemi.se/flodessok/floden/kemamne_eng/polyeten_eng.htm
http://en.wikipedia.org/wiki/Polyethylene
http://www.answers.com/Q/What_are_advantages_and_disadvantages_of_polythene
Phenolic Resin & Adhesives
This document provides information on phenolic resin adhesives and epoxy adhesives. It discusses that phenolic resins are thermoset polymers produced from reactions of phenol or substituted phenols with formaldehyde. They are used for applications like bonded abrasives, coated abrasives, and friction elements. The document also describes the synthesis and applications of epoxy resins, which include their reaction with hardeners, modifiers, fillers to produce one component or two component adhesives. Examples of formulations for general purpose, quick cure, and one component epoxy adhesives are also provided.
Silicon rubber pankaj kumar das
Silicon rubber is an inorganic polymer composed of silicon and oxygen in its backbone. It is synthesized from dimethyldichlorosilane through hydrolysis and polycondensation reactions. Silicon rubber has excellent thermal stability, flexibility even at low temperatures, and resistance to chemicals and weathering. It is widely used in medical applications like tubing and implants due to its biocompatibility, as well as in mechanical applications for seals, gaskets and vibration damping.
Polystyerene
Polystyrene is a hard, transparent synthetic resin produced from styrene monomer. It can be solid or foam and is used widely in food packaging, construction insulation, and other applications. Polystyrene has good insulation properties but is flammable and allows oxygen and water vapor to pass through. It is produced in various forms including sheets, molded blocks, and extruded foam boards. Common uses include below-grade foundation insulation, cavity wall insulation, and roof insulation. However, polystyrene is non-biodegradable and can harm wildlife if released into the environment.
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polystyrene
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TIME DIVISION MULTIPLEXING TECHNIQUE FOR COMMUNICATION SYSTEM
Time Division Multiplexing (TDM) is a method of transmitting multiple signals over a single communication channel by dividing the signal into many segments, each having a very short duration of time. These time slots are then allocated to different data streams, allowing multiple signals to share the same transmission medium efficiently. TDM is widely used in telecommunications and data communication systems.
### How TDM Works
1. **Time Slots Allocation**: The core principle of TDM is to assign distinct time slots to each signal. During each time slot, the respective signal is transmitted, and then the process repeats cyclically. For example, if there are four signals to be transmitted, the TDM cycle will divide time into four slots, each assigned to one signal.
2. **Synchronization**: Synchronization is crucial in TDM systems to ensure that the signals are correctly aligned with their respective time slots. Both the transmitter and receiver must be synchronized to avoid any overlap or loss of data. This synchronization is typically maintained by a clock signal that ensures time slots are accurately aligned.
3. **Frame Structure**: TDM data is organized into frames, where each frame consists of a set of time slots. Each frame is repeated at regular intervals, ensuring continuous transmission of data streams. The frame structure helps in managing the data streams and maintaining the synchronization between the transmitter and receiver.
4. **Multiplexer and Demultiplexer**: At the transmitting end, a multiplexer combines multiple input signals into a single composite signal by assigning each signal to a specific time slot. At the receiving end, a demultiplexer separates the composite signal back into individual signals based on their respective time slots.
### Types of TDM
1. **Synchronous TDM**: In synchronous TDM, time slots are pre-assigned to each signal, regardless of whether the signal has data to transmit or not. This can lead to inefficiencies if some time slots remain empty due to the absence of data.
2. **Asynchronous TDM (or Statistical TDM)**: Asynchronous TDM addresses the inefficiencies of synchronous TDM by allocating time slots dynamically based on the presence of data. Time slots are assigned only when there is data to transmit, which optimizes the use of the communication channel.
### Applications of TDM
- **Telecommunications**: TDM is extensively used in telecommunication systems, such as in T1 and E1 lines, where multiple telephone calls are transmitted over a single line by assigning each call to a specific time slot.
- **Digital Audio and Video Broadcasting**: TDM is used in broadcasting systems to transmit multiple audio or video streams over a single channel, ensuring efficient use of bandwidth.
- **Computer Networks**: TDM is used in network protocols and systems to manage the transmission of data from multiple sources over a single network medium.
### Advantages of TDM
- **Efficient Use of Bandwidth**: TDM all
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Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
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Polycarbonate
- 2. Presented by : Shadi Razmara department of Chemical engineering Isfahan university of technology Isfahan – Iran 2017 1/20
- 3. History What is pc ? Chemical structure Synthesis Properties applications content 2/20
- 4. PC was developed in 1953 by the German scientist "Hermann Schnell" who was chemist in German company "Bayer" 2-PC was introduced in United States Of America in 1960 by the general electric company History 3/20
- 5. What is pc General polymer Thermoplastic Containing carbonate groups High electrical & heat resistance non-flammable Lightweight 4/20
- 6. What is pc Good transparency Can be recycled most popular trade name is LEXAN Anti UV Impact resistance(unbre akable) Very pliable(formed at room temperature) 5/20
- 8. Chemical structure Bisphenol A + carbonate group Contain 2 aromatic rings(for stiff backbone) Amorphous structure Most often synthesized from bisphenol A & phosgene (COCl2) 7/20
- 9. synthesis Polymerizasion Step 1 Bisphenol A are reacted with proton acceptors such as NaOH 8/20
- 10. synthesis Polymerizasion Step 2 The deprotonated bisphenol reacted with phosgene & a catalyst (often times Pyridine) in 25-35 ℃ 9/20
- 11. synthesis Polymerizasion Step 3 Chloride anions are eliminated in order to react more bisphenol & phosgene 10/20
- 12. properties • Melt temperature 220-230 ℃ • Specific heat capacity 1.2-1.3 KJ/kg.K • Density 1.19 g/cm3 • Coefficient of friction 0.31 • Speed of sound 2270 m/s • Glass transition tem. 147 ℃ • linear thermal expansion co • Compressive strength 80 Mpa 65 − 70 ∗ 10−6 11/20
- 14. application safety Bullet proof glass Impact resistance Polycarbonate sheet is as clear as glass & 250 times stronger. It‘s also 30 times stro nger than Acrylics. 13/20
- 15. application UV protection Light weight 14/20
- 16. application Eye lenses Polycarbonate lenses are one Of the lightest, thinnest and safest lenses on the market today Anti UV 15/20
- 17. application headlamp bottles Compact disc 16/20
- 21. o Scratches easily o high price ) It is much more expensive than the other plastics or the glass ( o Manufacturing process is not very environm entally friendly (high temp & phosgene( o it has yellowing over time disadvantage 20/20
- 22. October 2017