This document provides an overview of plastics and rubber, including their history, key developments, types, properties, manufacturing processes, and recycling. Some of the main points covered include:
- The first man-made plastic was Parkesine created in 1862; major early developments included celluloid, Bakelite, and nylon.
- Thermoplastics can be remelted and remolded, while thermosets chemically decompose when heated.
- Plastics are lightweight, durable, versatile materials but take a long time to decompose without proper disposal and recycling.
Brief lesson on where plastics come from, the difference between thermoplastics and thermosettings, types of thermoplastics and thermosettings products and how plastics are shaped.
Brief lesson on where plastics come from, the difference between thermoplastics and thermosettings, types of thermoplastics and thermosettings products and how plastics are shaped.
Polymethylmethacrylate (POL-ee-meth-uhl-meth-AK-rill-ate) is a clear thermoplastic resin used to make windshields, visors, coatings for baths, advertising signs, and contact lenses. It is also widely used in dentistry and medicine. A thermoplastic resin is one that becomes soft when heated and hard when cooled. It can be converted back and forth any number of times between the solid and liquid states by further heating and cooling.
Learn about the nine primary physical properties of a rubber compound: hardness, tensile strength, modulus, elongation, tear resistance, abrasion resistance, compression set resistance, resilience and specific gravity. This presentations offers detailed information on each property, why it is important and how it is measured.
Plastic manufacturing "forming and shaping plastics"Ayush Mathur
how plastic products are manufactured?
what are the processes involved in manufacturing of these products?
what are the various machine tools used?
what are the various types of plastics and what is resin?
what are the diffrent steps in manufacturing?
Get all these answers in this presentation.
This topic relates to polymer structure and types of plastic. It also explains the usage and mechanical properties of thermo plastic, thermosetting plastic and the process of making plastic products.
Polymethylmethacrylate (POL-ee-meth-uhl-meth-AK-rill-ate) is a clear thermoplastic resin used to make windshields, visors, coatings for baths, advertising signs, and contact lenses. It is also widely used in dentistry and medicine. A thermoplastic resin is one that becomes soft when heated and hard when cooled. It can be converted back and forth any number of times between the solid and liquid states by further heating and cooling.
Learn about the nine primary physical properties of a rubber compound: hardness, tensile strength, modulus, elongation, tear resistance, abrasion resistance, compression set resistance, resilience and specific gravity. This presentations offers detailed information on each property, why it is important and how it is measured.
Plastic manufacturing "forming and shaping plastics"Ayush Mathur
how plastic products are manufactured?
what are the processes involved in manufacturing of these products?
what are the various machine tools used?
what are the various types of plastics and what is resin?
what are the diffrent steps in manufacturing?
Get all these answers in this presentation.
This topic relates to polymer structure and types of plastic. It also explains the usage and mechanical properties of thermo plastic, thermosetting plastic and the process of making plastic products.
Sustainability of the product is becoming a crucial factor for success in the market. Sustainability theory and methods are quite general. This research constitutes a serious attempt to assess the sustainability of plastic sheet piling, and calculate the product carbon footprint. In the case of plastic sheet piling no significant previous research has been done to address sustainability. The product lifecycle including stages such as raw material production, manufacturing, transportation, installation, and disposal/recycling, and its related supply chain have been analysed in detail to identify those factors that have impact on the product carbon footprint and the three main dimensions of sustainability: environmental, social and economic. The installation stage, which is not normally addressed in this kind of studies, has been assessed by the development of a case study.
this is my prsentation of Plastic Process and Processing Parameter in manufacturing process. here discussed moulding process for plastic, plastic injection moulding, machine parts and procedure, material used to making mould and blow moulding process, thermoforming process, vacuum forming process, and application
How to select a plastic injection molding machine.Naik Devang
Buying a PIMM is not a small investment. Too much machine for the job at hand is wasteful. Too little machine does not get job done. Careful matching of the jobs needs and the attributes of a PIMM is well worth the effort.
Many materials in day to day use are made from natural and synthetic polymers as constituents. Polymer based industries are products of research and development.
Intrduction to polymers in materials science and engineeringmojeedadisa
Introduction to Polymers in Materials Science and Engineering
Unveiling the Building Blocks of Our World
This presentation delves into the fascinating world of polymers, the ubiquitous materials that shape our everyday lives. We'll explore their fundamental characteristics, how they're formed, and the diverse applications they enable in materials science and engineering.
Key areas covered:
What are polymers? (definition, structure, types)
Unveiling the building blocks: monomers and polymerization
Natural vs. synthetic polymers: Exploring their origins
Tailoring properties for specific applications
Processing techniques: Bringing polymers to life
From concept to creation: Applications across industries
Join us as we discover the power of polymers and their remarkable impact on shaping our world!
Environmentally friendly polymer composites: our past, ongoing studies and fu...zenziyan
THE PLENARY PRESENTATION ON II INTERNATIONAL SCIENTIFIC CONFERENCE 'THE MODERN TECHNOLOGIES OF POLYMER MATERIALS OBTAINING AND PROCESSING' (TPM-2019) at November 06–08, 2019, LVIV, UKRAINE
Elastomeric materials that meet tough challenges
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Author: Dr. Banja Junhasavasdikul
Published: August 2022
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Rubber is a miracle elastomeric material for which there are hardly any alternatives
because of its elastomeric properties. Natural rubber and synthetic rubbers have been
developed to serve man-kind in sealing, transporting, conveying and containing solid, liquid
and gas that other materials find difficult to do.
How could we live in this world without rubber? How would we drive our cars without
rubber? Rubber products are everywhere and offer practical solutions for a wide variety of
design challenges.
Chemistry of plastics, rubber and resinsrita martin
Plastics any synthetic or semi-synthetic organic material includes chains of carbon, oxygen, sulfur or nitrogen. Rubber elastic substance divided into two groups natural, synthetic rubber. Resin is a natural or synthetic hydrocarbon secreted many plants
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
2. PLASTIC
A plastic material is any of a wide range of
synthetic or semi-synthetic organic solids that are
moldable.
Plastics are typically organic polymers of high
molecular mass, but they often contain other
substances. They are usually synthetic, most
commonly derived from petrochemicals but many
are partially natural.
3. Plastics History
First Plastic - Parkesine
The first man-made plastic was created by Alexander
Parkes who publicly demonstrated it at the 1862
Great International Exhibition in London. The
material called Parkesine was an organic material
derived from cellulose that once heated could be
molded, and retained its shape when cooled.
5. • Celluloid is derived from cellulose and alcoholized
camphor.
• John Wesley Hyatt invented celluloid as a substitute
for the ivory in billiard balls in 1868. He first tried
using collodion a natural substance, after spilling a
bottle of it and discovering that the material dried
into a tough and flexible film.
• However, the material was not strong enough to be
used as a billiard ball, until the addition of camphor, a
derivative of the laurel tree. The new celluloid could
be molded with heat and pressure into a durable
shape.
7. Formaldehyde Resins - Bakelite
• After cellulose nitrate, formaldehyde was the next
product to advance the technology of plastic.
Around 1897, efforts to manufacture white
chalkboards led to casein plastics (milk protein
mixed with formaldehyde) Galalith and Erinoid
are two early tradename examples.
• In 1899, Arthur Smith received British Patent
16,275, for "phenol-formaldehyde resins for use
as an ebonite substitute in electrical insulation",
the first patent for processing a formaldehyde
resin.
8. • In 1899, Arthur Smith received British Patent
16,275, for "phenol-formaldehyde resins for use
as an ebonite substitute in electrical insulation",
the first patent for processing a formaldehyde
resin. However, in 1907, Leo Hendrik Baekeland
improved phenol-formaldehyde reaction
techniques and invented the first fully synthetic
resin to become commercially successful,
tradenamed Bakelite.
10. Timeline - Precursors
• 1839 - Natural Rubber - method of processing
invented by Charles Goodyear
• 1843 - Vulcanite - Thomas Hancock
• 1843 - Gutta-Percha - William Montgomerie
• 1856 - Shellac - Alfred Critchlow, Samuel Peck
• 1856 - Bois Durci - Francois Charles Lepag
11. Timeline - Beginning of the
Plastic Era with Semi Synthetics
• 1839 - Polystyrene or PS discovered - Eduard
Simon
• 1862 - Parkesine - Alexander Parkes
• 1863 - Cellulose Nitrate or Celluloid - John
Wesley Hyatt
• 1872 - Polyvinyl Chloride or PVC - first created by
Eugen Baumann
• 1894 - Viscose Rayon - Charles Frederick Cross,
Edward John Bevan
12. Timeline - Thermosetting
Plastics and Thermoplastics
• 1908 - Cellophane ® - Jacques E. Brandenberger
• 1909 - First true plastic Phenol-Formaldehyde tradenamed
Bakelite - Leo Hendrik Baekeland
• 1926 - Vinyl or PVC - Walter Semon invented a plasticized
PVC.
• 1927 - Cellulose Acetate
• 1933 - Polyvinylidene chloride or Saran also called PVDC -
accidentally discovered by Ralph Wiley, a Dow Chemical lab
worker.
• 1935 - Low-density polyethylene or LDPE - Reginald Gibson
and Eric Fawcett
• 1936 - Acrylic or Polymethyl Methacrylate
13. • 1937 - Polyurethanes tradenamed Igamid for plastics materials
and Perlon for fibers. - Otto Bayer and co-workers discovered
and patented the chemistry of polyurethanes
• 1938 - Polystyrene made practical
• 1938 - Polytetrafluoroethylene or PTFE tradenamed Teflon - Roy
Plunkett
• 1939 - Nylon and Neoprene considered a replacement for silk
and a synthetic rubber respectively Wallace Hume Carothers
• 1941 - Polyethylene Terephthalate or Pet - Whinfield and
Dickson
• 1942 - Low Density Polyethylene
• 1942 - Unsaturated Polyester also called PET patented by John
Rex Whinfield and James Tennant Dickson
• 1951 - High-density polyethylene or HDPE tradenamed Marlex -
Paul Hogan and Robert Banks
• 1951 - Polypropylene or PP - Paul Hogan and Robert Banks
14. • 1953 - Saran Wrap introduced by Dow
Chemicals.
• 1954 - Styrofoam a type of foamed
polystyrene foam was invented by Ray
McIntire for Dow Chemicals
• 1964 - Polyimide
• 1970 - Thermoplastic Polyester this includes
trademarked Dacron, Mylar, Melinex, Teijin,
and Tetoron
• 1978 - Linear Low Density Polyethylene
• 1985 - Liquid Crystal Polymers
15. Plastic Products
1.Plastic Garbage Bags
A bin bag or bin liner or garbage bag, or trash
bag (American English) is a disposable bag used
to contain rubbish (British English) or trash
(American English).
16. 2. SILLY PUTTY
Silly Putty is a toy based on silicone polymers which
display unusual physical properties. It bounces, but
breaks when given a sharp blow and can also flow
like a liquid. It contains a viscoelastic liquid silicone,
a type of non-Newtonian fluid, which makes it act
as a viscous liquid over a long time period but as an
elastic solid over a short time period.
17. 3. VELCRO
Velcro is a company that produces the first commercially marketed
fabric hook-and-loop fastener typically, two lineal fabric strips. The
first component features tiny hooks; the second features even
smaller and "hairier" loops. When the two components are pressed
together, the hooks catch in the loops and the two pieces fasten or
bind temporarily. When separated, by pulling or peeling the two
surfaces apart, the velcro strips make a distinctive "ripping" sound.
18. Types Of Plastics
• The response of a polymer to mechanical forces at
elevated temperature is related to its dominant
molecular structure.
• One classification of polymers is according to its
behavior and rising temperature. Thermoplastics
and Thermosets are the 2 categories.
• A THERMOPLASIC is a polymer that turns to a liquid
when heated and freezes to a very glassy state when
cooled sufficiently.
• Most thermoplastics are high-molecular-weight
polymers whose chains associate through weak Van
der Waals forces (polyethylene); stronger dipole-
dipole interactions and hydrogen bonding (nylon).
23. • Thermoplastic polymers differ from
thermosetting polymers (Bakelite, vulcanized
rubber) since thermoplastics can be
remelted and remolded.
• Thermosetting plastics when heated, will
chemically decompose, so they can not be
recycled. Yet, once a thermoset is cured it
tends to be stronger than a thermoplastic.
• Typically, linear polymers with minor
branched structures (and flexible chains) are
thermoplastics. The networked structures
are Thermosets.
30. 3. Compounding the polymer into a material that
can be used for fabrication.
31. 4. Molding or shaping the plastic into its final
form.
32. Properties Of Plastics
• Lightweight
• Resistance to breakage
• Insulating capacity (electrical, thermal and acoustic)
• Ease of handling and safety
• Versatility
• Recyclability
• Usefulness
• Simple, cheap manufacturing
• Impermeability (water, light, gases)
• Does not conduct electricity (excellent for cables,
plugs)
33. Advantages
• It is cheap and easy to buy.
• Hard plastics can be used in making chairs, toys
etc.
• Can be putted in other materials and strengthens
them.
• Easy to clean and hard to break, you can use it to
store water and food.
• Can be used in all types of season and weather
even if its summer or raining.
• Can be recycled into another product.
• Can be used in surgeries.
34. Disadvantages
• It takes a hundred of years to decompose.
• Hard to dispose properly.
• It is made from nonrenewable resources of Earth.
• Can’t stand up because of its lightness.
• Are not biodegradable.
• Number one flood causing material.
• Recycling is very Expensive.
35. Recycling Plastic
• Plastic recycling is a process in which old plastics
is turned into another more useful products.
Since plastics can be considered indestructible or
simply does not break down easily. It is also the
number one trash of humans in landfills which
took a lot of space.
• One way to reduce it is to recycle. From the word
recycling itself I know you have already an idea
what will they do to it. The plastics are brought
back to the factories where they do recycling and
turned to another products. Some can be turned
into trashcans, pots, papers and many more.
37. Types Of Recycling Processes
1. Mechanical Recycling
The recycling in which plastics are grouped, then
melted, shredded and molded into new shapes
creating a new product.
2. Chemical Recycling
The recycling in which plastics are melted altering
some chemical properties to create a new product.
38. Biodegradable Plastics
• This is the another way to solve our environmental
problems from plastics, this replaces the non-
biodegradable plastics into new breed called bioplastic.
• These breed of plastics are commonly made from plants
such as corn starch, cane sugar, potato starch and native
wild grasses.
• It also helps reducing the use of nonrenewable
resources of Earth by using renewable ones which
benefits both humans and nature.
• Disposing it properly is the best way to help in reducing
pollution and minimizing the dependence on fossil fuels.
40. Plastic Recycling Symbols
In 1988 the Society of the Plastics Industry
developed a numeric code to provide a uniform
convention for different types of plastic containers.
These numbers can be found on the underside of
containers.
1. PET; PETE (polyethylene terephthalate): plastic water and
Soda bottles.
2. HDPE (high density polyethylene): laundry/dish detergent
3. V (Vinyl) or PVC: Pipes, shower curtains
4. LDPE (low density polyethylene): grocery bags, sandwich
bags
5. PP (polypropylene): Tupperware®, syrup bottles, yogurt
cups,
6. PS (polystyrene): Coffee cups, disposable cutlery
7. Miscellaneous: any combination of 1-6 plastics
41. Rubber
Rubber can be described in two ways :-
1. Natural rubber is a substance obtained
from the milky juice, called latex,
produced by a number of different
kinds of plants.
2. Synthetic rubber, made by various
chemical manufacturing processes, is
similar to natural rubber.
42. Natural Rubber
Natural rubber, also called India rubber or, as
initially produced, consists of suitable polymers of
the organic compound isoprene, with minor
impurities of other organic compounds plus water.
• Currently, rubber is harvested mainly in the form
of the latex from certain trees.
• The latex is a sticky, milky colloid drawn off by
making incisions into the bark and collecting the
fluid in vessels in a process called "tapping".
43. • The latex then is refined into rubber ready for
commercial processing.
• Natural rubber is used extensively in many
applications and products, either alone or in
combination with other materials.
• In most of its useful forms, it has a large stretch
ratio, high resilience, and is extremely
waterproof.
46. 2. Liquid Latex Extracted Is Poured Into a Tray
with Spikes So That after Drying Latex can Be
easily taken out.
47. 3.The Tray is then put in a Latex Hardening
And Drying Machine (LHDM)
48. 4. After Hardening and Getting Dried The
Latex We get a Cuboid Of Natural Rubber.
49. Synthetic Rubber
• Synthetic rubber is created from petroleum and is
classified as an artificial elastomer.
• This means that it is able to be deformed without
sustaining damage, and can return to its original
shape after being stretched.
• Synthetic rubber has many advantages over
natural rubber, and is used in many applications
due to its superior performance.
• The use of synthetic rubber is much more
prominent than natural rubber in most
industrialized nations.
56. Used In Shoes, Stationery, Other Lifestyle products etc.
57. Properties of Rubber
1. Physical Properties
• Non reactive
• Chemically Resistant to many fluids including
many water, weak acids & alkalis
• Non conductive
• Poor conductor of heat & electric
• Elastic
• Tough
• Electric resistant
• Electric insulator
58. 2. Chemical Properties
• Polymers
• Consists of isoprene molecules fitted together in
loosed chains
• Consisting long chains of one or more type of
molecules
• Contain long chains of hydrogen and carbon
molecules
• Rubber go through vulcanization through adding
sulfur which result in a hard, durable material with
great mechanical properties.
• This create a chemical links between the chains.
59. Advantages Of Rubber
• Rubber is not only elastic, but is also waterproof
and is a good electrical insulator.
• Natural rubber is resilient and is resistant to
tearin.
• Some types of rubber are resistant to oils,
solvents, and other chemicals.
• SBR (STYRENE BUTADIENE RUBBER) RUBBER
provides good abrasion, wear, and tensile
qualities.
• Rubber is resistant to ozone, sunlight, oxidation
and many petroleum derivatives.
60. • It also exhibits excellent resistance to ozone,
oxidants, and severe weather conditions,
thereby making it an outstanding material for
outdoor applications.
• Other characteristics include excellent color
stability, heat resistance, and dielectric qualities.
61. Disadvantages Of Rubber
• Low-cost latex products generally shrink.
• Making molds with latex rubber is slow and time-
consuming.
• Latex molds are generally not suitable for casting
resins.
• Has offensive odour.
• Silicones are generally high in cost. They are also
sensitive to substances, and do not have a long
library life.
• Polysulfide rubber costs higher than latex.
62. • Needed to cleaned it often to be kept clean.
• Detergent & other abrasive cleaning liquid which
may discolor surface.
• Grease will have a drastic negative effect if not
wiped up.
63. Recycling Rubber
Why reclaim or recycle rubber?
Rubber recovery can be a difficult process. There are many
reasons, however why rubber should be reclaimed or
recovered;
• Recovered rubber can cost half that of natural or
synthetic rubber.
• Recovered rubber has some properties that are
better than those of virgin rubber.
• Producing rubber from reclaim requires less energy
in the total production process than does virgin
material.
• It is an excellent way to dispose of unwanted rubber
products, which is often difficult.
64. • It conserves non-renewable petroleum products,
which are used to produce synthetic rubbers.
• Recycling activities can generate work in
developing countries.
• Many useful products are derived from reused
tyres and other rubber products.
• If tyres are incinerated to reclaim embodied
energy then they can yield substantial quantities
of useful power. In Australia, some cement
factories use waste tyres as a fuel source.