Polymers & Polymerisation

Polymers

A monomer is a molecule that can join with other molecules to form a chain of molecules. A chain of monomers (or molecules) is called a polymer. 

Chains of polymers then bond or stick together to form stuff like cellulose, the woody stuff in plants.

Natural polymers are created as part of ongoing biological processes.

Read more about monomers and polymers here.

Polymerisation

However polymers can be made, by wo/men in labs, chemists. Here they create synthetic polymers and stick them together to create a huge range of products.

Some may copy the polymers found in nature but others, like plastic, are completely new – they have no natural equivalent.

The process of making polymers is called polymerisation.

 Most synthetic polymers that we use today are made from hydrocarbons derived from oil.

However as oil becomes more scarce and more expensive, synthetic polymers are being derived from all manner of substances including corn, potatoes and even chicken feathers.

Fun Quote

“nature has been knitting polymers since the beginning of life. Every living organism contains these molecular daisy chains. The cellulose that makes up the cell walls in plants is a polymer. So are the proteins that make up our muscles and our skin and the long spiraling ladders that hold our genetic destiny, DNA. Whether a polymer is natural or synthetic, chances are its backbone is composed of carbon, a strong, stable, glad-handing atom that is ideally suited to forming molecular bonds. Other elements—typically oxygen, nitrogen, and hydrogen—frequently join that carbon spine, and the choice and arrangement of those atoms produces specific varieties of polymers. Bring chlorine into that molecular conga line, and you can get polyvinyl chloride, otherwise known as vinyl; tag on fluorine, and you can wind up with that slick nonstick material Teflon.”

An excerpt from Susan Freinkel‘s book, Plastic: A Toxic Love Story.

 

 

 

 

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Epoxy Resin

To understand plastic you need a lot of time and a good working knowledge of chemistry at the very least. Currently I am trying to find out what epoxy resin actually is. Sigh! Here’s what I got….

It is a thermoset plastic which means it can only be heated and shaped once.

Most epoxy resins are petroleum derived but some plant derived sources are now becoming commercially available such as plant derived glycerol.

Properties Good electrical insulator, hard, brittle unless reinforced, resists chemicals well

Principal uses Casting and encapsulation, adhesives, bonding of other materials. And lining tin cans.

Epoxy resin can be mixed with additives, plasticizers or fillers to create different products with a range of properties Use of blending, additives and fillers is often referred to as formulating.”

Bisphenol A (BPA)

And of course the one everyone is concerned about ….. BPA is an integral part of most epoxy resins.

“The most common and important class of epoxy resins is formed from reacting epichlorhydrin with bisphenol A to form diglycidyl ethers of bisphenol A.”

Many consider BPA to be a health hazard.

Nearly all tin cans are lined with epoxy resin. and have been since the 50s. The liner can be white or yellow or transparent in which case it is undetectable. BPA can leach from the liner into the contents of the can. For more on this read Why Does My Can Have A Liner & Is It Bad For Me.

Other Resins

  • Bisphenol F epoxy resin
  • Novolac epoxy resin
  • Aliphatic epoxy resin
  • Glycidylamine epoxy resin
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Hydrocarbons

Hydrocarbon is a molecule that only contains hydrogen and carbon atoms, joined together by covalent bonds. Remember that a covalent bond is a shared pair of electrons.

These compounds may be simple with only a few atoms or more complex with more.

The compounds come in different forms. Methane the smallest hydrocarbon is a gas lighter than air while tar, a much larger compound, is thick and gloopy.

The ability of carbon atoms to bond strongly to each other allows them to form an almost unlimited variety of chains, rings, and other structures that form the backbones of organic molecules. Since each atom can form four bonds, these backbones include other elements, such as hydrogen. The compounds are flammable, since the two elements they contain will combine easily with oxygen in the air, releasing energy. Fossil fuels, such as oil and natural gas, are naturally occurring mixtures of hydrocarbons; coal also contains some, although it is mostly just carbon.

In organic chemistry, a hydrocarbon is categorised as an organic compound. {Organic compounds are the complex compounds of carbon. Because carbon atoms bond to one another easily, the basis of most organic compounds is comprised of carbon chains that vary in length and shape. Hydrogen, nitrogen, and oxygen atoms are the most common atoms that are generally attached to the carbon atoms.}

Hydrocarbons contain a lot of energy.

Hydrocarbons like crude oil and natural gas are harvested for their high energy content.

Crude oil can be distilled to separate different hydrocarbons including petrol.

Carbon is great at bonding and so can easily forms polymers. A polymer is a large molecule that is made up of many smaller, repeating molecules, called monomers, which are joined together by covalent bonds.

Hydrocarbon chains can be broken and rearranged in different ways.  According to B.P. “the hydrocarbon compound is the most versatile on the chemical charts. It can make an estimated 2.5 million possible combinations. Longer, heavier molecules can be transformed into lighter ones and vice versa.”

And so they can be used to make new and different products such as plastic, a wholly synthetic product made from a natural resource.

Hydrocarbons are often used to make polymers.

Many hydrocarbons occur in nature. In addition to making up fossil fuels, they are present in trees and plants,

Disclaimer

I suppose I must have studied chemistry at school. I seem to remember some high jinks with a bunsen burner but nothing else. I now realize that you can understand nothing about the practical world without some basic knowledge of how it works. So I am trying to teach myself chemistry via Google. I know I get it wrong sometimes. Do bear that in mind when you read these fumbling explanations that I am learning as I go. Any help gratefully received.

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Polypropylene

Polypropylene (PP) plastic code 5

It is the second most important plastic after polyethylene.

It is a thermoplastic polymer that is rugged and unusually resistant to many chemical solvents, bases and acids.

It is used to make soup pots, margarine tubs, most bottle tops, waterproof clothing, carrier bags, ropes, non woven fibre products like the fluffy cottonwool type stuff used in tampons and nappies.

Does not biodegrade.

UK Collection Rates for recycling.Not generally collected for household recycling, although it has good potential.However, mixed plastic recycling is expected to be under way within five years. (please note this information is always changing. Updates will be posted here first so you may wish to double check.)

It is expected to net US$145 billion by 2019 and the sales of this material are forecast to grow at a rate of 5.8% per year until 2021.

In 2013, the global market for polypropylene was about 55 million metric tons. Wikkipedia.

Polypropylene is made from propylene. This in turn is made from propane.

Propane is derived from hydrocarbons

Hydrocarbon chains are refined by cracking and polymerising.

Very basically cracking breaks the existing chains and polymerisation is remixing them into something new.

Using high-temperature furnaces, propane is cracked into propylene,

Using a catalyst, a reactor and some heat propylene joins together to create a polymer called polypropylene.

Propane can be derived from Naptha ( which is distilled from crude oil)

90% of propylene is made from oil though that figure is rapidly changing as more is made from shale gas as a result of fracking.

“North America plans to build 6 new plants to to make “on purpose” propylene from propane “In the past the price of propylene and propane were so close in the U.S. that it wasn’t cost effective to dehydrogenate propane, but now with low cost propane from shale gas, it is. “

Polypropylene was discovered in  1951 by two chemists working for Phillips Petroleum Company.

In 2008, researchers in Canada asserted that quaternary ammonium biocides and oleamide were leaking out of certain polypropylene labware, affecting experimental results.

 

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Thermoplastics and Thermoset Plastics

Plastics are divided into thermoplastics and thermoset plastics.

Thermoplastics can be heated and shaped many times.

Thermoplastics pellets soften when heated and become more fluid as additional heat is applied. The curing process is completely reversible as no chemical bonding takes place. This characteristic allows thermoplastics to be remolded and recycled without negatively affecting the material’s physical properties.

Thermoset plastics can only be heated and shaped once.

Thermoset materials are usually liquid or malleable prior to curing and designed to be molded into their end form, or used as adhesives. Others are solids like that of the molding compound used in semiconductors and integrated circuits (IC

Thermoset plastics contain polymers that cross-link together during the curing process to form an irreversible chemical bond. The cross-linking process eliminates the risk of the product remelting when heat is applied, making thermosets ideal for high-heat applications such as electronics and appliances.

These polymers are highly cross-linked, which means the molecules have extremely strong chemical bonds. Once you’ve initially heated them up to set them into the shape you want – hence the name “thermoset” – they’re irreversibly bound. That means they’re much stronger than thermoplastics, but also that heating them up again won’t break down the bonds in a way that enables you to usefully reshape them, as with thermoplastics. It’ll just char them and crack them instead.

Thermoset plastics that can be remoulded and recycled several times over when heated to about 100ºC are possible, claim researchers in The Netherlands. 

The self-healing polymers make use of the Diels-Alder and Retro-Diels-Alder reactions between thermosetting polyketones and bis-maleimide, allowing the strong covalent bonds of the thermoset materials to be broken and reformed.

Examples of some thermoplastics.

Name Properties Principal uses
Polyamide (Nylon) Creamy colour, tough, fairly hard, resists wear, self-lubricating, good resistance to chemicals and machines Bearings, gear wheels, casings for power tools, hinges for small cupboards, curtain rail fittings and clothing
Polymethyl methacrylate (Acrylic) Stiff, hard but scratches easily, durable, brittle in small sections, good electrical insulator, machines and polishes well Signs, covers of storage boxes, aircraft canopies and windows, covers for car lights, wash basins and baths
Polypropylene Light, hard but scratches easily, tough, good resistance to chemicals, resists work fatigue Medical equipment, laboratory equipment, containers with built-in hinges, ‘plastic’ seats, string, rope, kitchen equipment
Polystyrene Light, hard, stiff, transparent, brittle, with good water resistance Toys, especially model kits, packaging, ‘plastic’ boxes and containers
Low density polythene (LDPE) Tough, good resistance to chemicals, flexible, fairly soft, good electrical insulator Packaging, especially bottles, toys, packaging film and bags
High density polythene (HDPE) Hard, stiff, able to be sterilised Plastic bottles, tubing, household equipment

Properties and uses of the thermoset plastics.

Name Properties Principal uses
Epoxy resin Good electrical insulator, hard, brittle unless reinforced, resists chemicals well Casting and encapsulation, adhesives, bonding of other materials
Melamine formaldehyde Stiff, hard, strong, resists some chemicals and stains Laminates for work surfaces, electrical insulation, tableware
Polyester resin Stiff, hard, brittle unless laminated, good electrical insulator, resists chemicals well Casting and encapsulation, bonding of other materials
Urea formaldehyde Stiff, hard, strong, brittle, good electrical insulator Electrical fittings, handles and control knobs, adhesives

http://www.bbc.co.uk/schools/gcsebitesize/design/resistantmaterials/materialsmaterialsrev3.shtml

Find out more about the above plastics and many others here .

Don’t know your PETS from your hamster. Think Polymer is a girl’s name? Check out this collection of definitions essential for understanding plastic!


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Degradable, biodegradable or compostable

So most plastics are made from oil and most plastics do not biodegrade. See how and why here…

And yet you will find plastics described as

  • degradable
  • biodegradable
  • compostable

What do these terms actually mean when applied to plastic?

Remember that

  • Most traditional, oil-based plastics do not biodegrade.
  • Biodegradable products break down as the result of the actions of naturally occurring microorganisms, such as fungi or bacteria, over a time.
  • Plastic breaks, tears and cracks. It weathers and sunlight makes it brittle, It falls apart – it degrades – but only into smaller pieces of plastic.
  • Find out more about the lifecycle of plastic here.

Degradable Plastic

All plastic degrade – i.e. they fall apart into smaller pieces of plastic. BUT when a plastic is described as degradable it could just describe the falling part process  OR it could mean t a degradation initiator has been added to make it fall apart faster.

Degradation Initiators and Bio-Degradable Plastics

But suppose there was a way of making plastic biodegradable? The industry argue that they can do just that by means of chemical additives known as degradation initiators. Very basically, these additives break the long unnatural plastic polymers into shorter recognisable polymers that microbes can attack and digest – or biodegrade (N.B. lots more research need to be done on this. It is by no means proven).

Because the degradation initiators are biologically  based they are sometimes described as biodegradable. So some traditional plastic bags have been labelled biodegradable.

This is  at best confusing if not deliberately misleading. This  is not the same process as natural biodegrading. Unlike truly biodegradable products they don’t always break down into harmless substances and may leave behind a toxic residue.

More so as  there are some compostable plastics which are also described (correctly) as  biodegradable which do actually compost down into biomass.

Read more about degradation initiators here.

Compostable Biodegradable Plastics

Truly biodegradable plastics are compostable.

Biodegradable products break down through a naturally occurring microorganism into simple, stable compounds which can be absorbed into the ecosystem. To be classed compostable, items must biodegrade within a certain time (around the rate at which paper biodegrades) For a man-made product to be sold as compostable, it has to meet certain standards. One such is the European Norm EN13432.

Compostable Plastics  meet all of these criteria. You can find out more here.

Infographic

Yes they have a vested interest making as they do compostable plastic goods but the info still stands.

Vegware factsheet

 

 

 

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Compostable Plastics

Plastic was the name given to early synthetic products such as cellophane,  that were derived from cellulose. These plastics  were biodegradable. Then they learnt how to make similar products from oil. Or rather from the bits of crude left over after they had finished making petrol. The same name was then given the oil derived product. But there were crucial differences. This new product was  made in a very different way and did NOT biodegrade.Since then yet more “plastics” have hit the market. Made from all kinds of things. Some from plant starch and some are certified compostable.

To conclude;
Currently, non- biodegradable, oil derived plastics are the most commonly used and so we tend to ascribe their qualities to all types of plastic.
In fact plastics can be made in a variety of ways from a variety of materials; shale gas, oil, plants even chicken feathers;
And different plastics have very different qualities. Some plastics do biodegrade and are certified compostable
Want to know more about plastic? Read up here

Biodegradable, Compostable Plastics

Just to remind you:
What is biodegradable? Biodegradable products break down through a naturally occurring microorganism into simple, stable compounds which can be absorbed into the ecosystem. More about biodegrading here
What is compostable? To be classed compostable, items must biodegrade within a certain time (around the rate at which paper biodegrades), and the resulting biomass must be free of toxins, able to sustain plant life and be used as an organic fertilizer or soil additive.
For a man-made product to be sold as compostable, it has to meet certain standards. One such is the European Norm EN13432.
You can find out more here.

Home Or Industrial Compostable?

Home Composting
Composting is usually done on a small scale and most people will be familiar with the concept of a backyard heap or garden compost where household waste is rotted down into garden mulch.
Industrial composting
However large-scale schemes are becoming increasingly popular. In the UK communities band together to compost a whole street is worth of waste. Even city councils are getting in on the act.
These larger projects are sometimes called industrial composting

The difference is is that industrial composting is a lot hotter and can work more quickly.

Home Compostable?
Many products ( especially compostable plastics), have been tested under industrial composting conditions. Therefore, while a product might be classed as both biodegradable and compostable, it might not break down in a backyard compost bin.
That said I have composted many such products in my own bin.

Compostable Plastic Products

These compostable plastics, like oil derived, are extremely versatile.
They can be thin and flimsy which means they can be used to make

PLA Compostable Plastic Bags
And liners to for paper cups to make them waterproof.

They can be harder and more rigid making them ideal for making

Disposable Cutlery 
Straws

Deli pots
Rigid packaging for food
Bottles

And longer lasting products like
Phone cases
Or sponges

See a wide range of compostable products HERE

Compostable Plastics Types
Cellulose derived plastics such as Cellophane.
Starch based PLA plastics. They are certified compostable.
Polyhydroxyalkanoates or PHAs  are linear polyesters produced in nature by bacterial fermentation of ­sugar or lipids.
chicken feathers bioplastic.

Composting Plastic At Home
While most agree that PLA plastic is indeed compostable, many say that it can only composted in large scale municipal schemes.
They are wrong. I have been composting plastics for years.
Read more HERE

To be sure you are using a compostable plastic get one that has been certified compostable. Check out the logo.

Compostable Plastic Products

See a wide range HERE

A Note On Bioplastics
Most compostable plastics are also bioplastics. Bioplastics are made from natural materials such as corn starch.
However not all are compostable. For example ethane based plastics as used Coca-Cola’s PlantBottle which replaces 30 percent of the ethanol in their normal polyethylene terephthalate (PET) plastic bottle with 30 percent plant-derived ethanol. This means the bottle is still considered PET and can be recycled but is NOT biodegradable. Find out more here.

Other Plastics
There is research being done into developing a compostable, oil-derived plastic. Watch this space BUT don’t fall for the old *biodegradable plastic bag trick see below.

*Compostable versus biodegradable plastics
You might see some plastics labelled described as biodegradable. You could be forgiven for thinking that this is the same as compostable plastic. It is not. Some “biodegradable plastics” are oil derived plastics with a degrading initiator added to make them fall apart (degrade) more  quickly. Unlike compostable plastics they don’t always break down into harmless substances and may leave behind a toxic residue. Read more here

More

Check out all our composting posts HERE
Want to know more about plastic? Read up here
See our big list of plastic types here

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Fabrics, Fibres & Yarns Index

In this post you can read  an introduction to fibres and fabrics or use the quick links to jump to detailed posts:

Jump To

Textiles and ultimately clothing start with fibres
Natural fibres
Coarse Fibres Are used for rope, string, sacking and industrial uses.Read more HEREFibres used for finer fabrics and yarnRead more HERE
Synthetic fibresRead more HERE
Regenerated FibresRead more HERE

Yarns and threads See links to plastic free products yarns HERE

Fabrics
Which fabric – why I prefer natural fabrics over synthetics here.
All about fabrics HERE
Buy FabricsHERE
Read all textile & wardrobe related posts HERE.

Introduction To Fibres, Yarns & Fabrics

Fibres (and then yarns and ultimately fabrics) can be can be natural, synthetic or chemically produced hybrid called regenerated fibres.

Definitions
Fibres are short fine hairs.
Fibres can be can be natural, synthetic or chemically produced hybrid called regenerated fibres.
Fibres can be twisted or spun into longer thread or yarn.
Threads can be woven or knitted into fabric.

Know Your Fibres

Natural Fibres
These are plant or animal derived.
They biodegrade

Synthetic fibres
These are man-made from chemicals many of which are petroleum derived.
Most are derived from oil and coal.
Most do not biodegrade.

Regenerated Fibres
The base material is cellulose that can be obtained from a range of sources including wood, paper, cotton fiber, or  bamboo. It is then converted through a chemical process into a fiber.
Some it is claimed are biodegradable. Some are not.

which Fibres

Why I prefer natural fabrics over synthetics here.

Yarns and threads

and what they are used for….
Yarns and threads usually take the name from the fibre in which they are spun.
they can be used as
string for tying
Thread for sewing
Yarn for knitting
See links to plastic free products HERE

Natural Yarn
Coarse Fibres Are used for rope, string, sacking and industrial uses.

they include:
Abaca can be used for rope,
coir from coconuts has a wide range of applications,
jute is used for sack cloth and
sisal for string.
As well as these traditional uses there are many new applications.
Read more HERE

Fibres used for finer fabrics and yarn include
Cotton used to make cotton
Flax is used to make linen. It is one of the strongest vegetable fibres.
Wools include
Sheep’s wool in a range of weights and qualities
Alpaca wool used to make high-end luxury fabrics.
Angora wool -The silky white wool of the Angora rabbit is very fine and soft, and used in high quality knitwear
Mohair also from the Angora goat.
Cashmere wool comes from cashmere goats and has great insulation properties without being bulky
Silk is strong and light weight.

Synthetic 
These are man-made from chemicals many of which are petroleum derived.
Acrylic, nylon and polyester come from oil and coal.
Most do not biodegrade.
Acrylic fibre resembles wool and so is used to replace that natural fibre.
Nylon is used as a silk substitute. It is a very fine and strong fibre so can be used to make ladies tights.
Polyester is one of the most popular man-made fibres. It is the same  Polyethylene terephthalat, (frequently shortened to PET or PETE and was formerly called PETP or PET-P), that is used to make bottles and a lot of other plastic stuff.

 

Regenerated 
The base material is cellulose that can be obtained from a range of sources including wood, paper, cotton fiber, or  bamboo. It is then converted through a chemical process into a fiber. One such in bamboo. Most bamboo fabric  is made using  chemical solvents such as sodium hydroxide (NaOH – also known as caustic soda or lye) and carbon disulfide  combined with multi-phase bleaching. Both sodium hydroxide and carbon disulfide have been linked to serious health problems. Others are looking extremely promising and are biodegradable.
They usually go under the trade names
Rayon
Bamboo Rayon
Viscose,
Modal
Tencel (lyocell)

Regenerated Fibres & fabrics  a very basic introduction

Fabrics

Threads can be woven or knitted into fabric.
They may be named after then yarn type. So cotton can be the fibre the yarn or the fabric. They may be named after the trade name like Modal.
See above for some fibre and yarn names.
But fabrics can also be subdivided into a huge number of additional categories. For example cotton fabric can be described as denim, lawn or muslin.
Woollen fabrics could be called tweed or
Silk comes under any number of of luscious sounding names including Charmeuse, Chiffon and Crepe de Chine.

Fabric may also be described by the technique used to make it. So jersey is a knitted fabric that could be made from cotton, silk or polyester.

Read more about

Clothing

Clothes are then made out of woven/knitted fabrics or knitted yarn.

More

Fibre Production

fibre pie chart

2013 figures

Global 2013 fibre production estimated at 85.5 million tons

• Global 2013 synthetic fibre production estimated at 55.8 million tons (i.e. excluding cotton, cellulosics and wool)

Natural Fibres
Cotton 25 million tons
wool production is around 2.1 million tonnes.
Silk 150 000 tonnes in 2006
Linen 147 000 tonnes of flax fibre 2007,
Alpaca 6 500 tonnes
Cashmere” after scouring and dehairing 6 500 tonnes
Mohair is estimated at around 5 000 tonnes a year, down from a high of 25 000 tonnes in the 1990s,
Angora is estimated at 2 500 to 3 000 tonnes
2009 figures  only – google let me down!

Carbon footprint

A study done by the Stockholm Environment Institute on behalf of the BioRegional Development Group  concludes that the energy used (and therefore the CO2 emitted) to create 1 ton of spun fiber is much higher for synthetics than for hemp or cotton:
KG of CO2 emissions per ton of spun fiber:

KG of CO2 emissions per ton of spun fiber:

crop cultivation

fiber production

TOTAL

polyester USA

0.00

9.52

9.52

cotton, conventional, USA

4.20

1.70

5.90

hemp, conventional

1.90

2.15

4.05

cotton, organic, India

2.00

1.80

3.80

cotton, organic, USA

0.90

1.45

2.35

Lots more great info on the carbon footprint of fabrics can be found here on this great blog.

More Information

Lots of outrageous statistics HERE

Read all our fabrics, apparel and yarn related posts HERE.

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Polyurethane

Polyurethane is made by reacting polyols and diisocyanates,

Polyols and diisocyanates are derived from crude oil and removed during the refining process just like gasoline.

Polyurethane foam can be flexible or rigid. Each form of polyurethane has many uses.

Most polyurethanes do not melt when heated but there are some (thermoplastic polyurethanes) that do.

Polyurethane formulations cover an extremely wide range of stiffness, hardness, and densities. These materials include:

Low-density flexible foam used in upholstery, bedding, and automotive and truck seating
Low-density rigid foam used for thermal insulation and RTM cores
Soft solid elastomers used for gel pads and print rollers
Low density elastomers used in footwear
Hard solid plastics used as electronic instrument bezels and structural parts
Flexible plastics used as straps and bands
lining the cups of brassieres.

Wikkipedia

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Methane

Methane is a short-lived climate pollutant with significant climate warming potential.

Methane gas, or biogas, is released  when organic material breaks down. But only when organic materials are so compacted there is no oxygen they break down anaerobically and produce methane.

This is why landfill sites produce methane and compost heaps do not

“Rotting stuff in a landfill undergoes anaerobic decomposition and produces methane.  A compost pile undergoes aerobic decomposition and requires oxygen (O2) for the process to work.  Because it is exposed to oxygen it produces CO2 (carbon dioxide) instead of methane.”

Cow farts are also made of methane.

Global methane emissions from landfill are estimated to be between 30 and 70 million tonnes each year. Most of this landfill methane currently comes from developed countries, where the levels of waste tend to be highest.

Over a 20 year period, one ton of methane causes 72 times more warming than one ton of carbon dioxide (CO2).

Methane can be  captured and used as fuel. This company is using methane gas from waste fish and chocolate to power their factory.

There are instructions here on how to harvest  methane at home (not from cow farts!)

Cut your methane production

Give up baked beans ….hahahahahahaa …..

Take up composting, the easiest way to cut your carbon footprint

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Chemicals, A definition

Plants and animals are organic everything else is inorganic
Inorganic things are made from chemicals. Chemicals are also found in organic things too.

Confused yet?
All matter contains chemicals – either single chemicals, such as pure water or oxygen or a mixture of chemicals – such as shampoos.
Elemental chemical composition of the average adult human body. Six elements  oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus account for 99% of the mass of the human body.

Chemicals are made from atoms and can be identified from the elements in the periodic charts
Some chemicals biodegrade – others do not.
Some chemicals occur naturally others are man made.
There are many new man made chemicals. Chemicals are also being combined a new and different ways with unknown consequences.

Chemophobia
The irrational fear of chemicals – usually a fear of man-made chemicals.
Rational Wiki “the line between natural and unnatural chemicals is a blurred one, or even totally non-existent. Many industrially important chemicals are produced via natural (biological) processes, such as fermentation to produce ethanol and monosodium glutamate, or extracted from plants and bacteria, such as caffeine extracted from coffee beans. Equally, these substances can be synthesised in a lab and purified in the same way. Despite absolutely no detectable differences between purified natural products and their synthesised counterparts, chemophobia postulates that the “artificial” one is worse.”

Plastic & Chemicals – Concerns
Some of the chemicals used to make plastic have not been passed as fit for human consumption. More worrying still they leach from plastic into us. Other plastics like PVC will, when burnt, release dioxin one of the most powerful carcinogens known. Plastic particles attract persistent organic Pollutants (POPs). POPs are a small set of toxic chemicals that remain intact in the environment for long periods and accumulate in the fatty tissues of animals. Bottom feeders eat the plastic pellets and so the POPs enter the food chain.

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Perfluorochemicals and plastic

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Phthalates.

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Endocrine System & Endocrine Disruptors

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Persistant Organic Pollutants

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Chemicals & Additives In Plastic

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Polychlorinated Biphenyls

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PTFE Non stick plastic

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PVC

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BPA

Bisphenol A or BPA is it is known to its chums is used in some thermal paper products such as till receipts. the ...
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Dioxins & Burning plastic

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N.B.

I have no wish to add to the massive amounts of misinformation out there.

Please note I am no chemist, I know nothing of the sciences. Any information here has been gleaned from the unreliable Google Mines and filtered through my total ignorance. I think it’s correct. If It’s not please do tell me.

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Plastic, an introduction

Plastic a definition
Plastics – the key points
Links to related posts

Plastics are  used to make everything from varnish to stockings, bottles to car parts by way of crisp packets and computers. They have revolutionized the world for the better but are now a major environmental pollutant. We use them everyday, for everything, even inserting it into our bodies. And yet we know very little about them.

This blog explores plastic the product, examines its impact and considers what we should and shouldn’t be using plastic for.

What is plastic?

Definition of plastic
If you look in the Oxford dictionary you will find plastic can be used to describe
substances or materials that “are easily shaped or moulded: ‘rendering the material more plastic’
1. 2.1 Offering scope for creativity:‘the writer is drawn to words as a plastic medium’
2. 2.2 Relating to moulding or modelling in three dimensions, or to produce three-dimensional effects:‘the plastic arts’
3. 2.3 (in science and technology) relating to the permanent deformation of a solid without fracture by the temporary application of force.
4. Artificial or unnatural: ‘a holiday rep with huge white teeth and a plastic smile’

But more commonly today it is used as a noun to refer to a “synthetic material made from a wide range of organic polymers such as polyethylene, PVC, nylon, etc., that can be moulded into shape while soft, and then set into a rigid or slightly elastic form: Oxford.
or Any of various organic compounds produced by polymerization, capable of being molded, extruded, cast into various shapes and films, or drawn into filaments used as textile fibres. Your Dictionary

So the term plastic was originally used to describe anything fluid, responsive capable of being molded or modelled; Clay could be plastic; sculpture could be described as plastic.

But more recently it has come to mean a certain type of product – a fluid, synthetic material that can be molded to make almost anything.

Are All Plastics The Same?

Plastic (when used to describe a product and not a quality) can be applied to  a huge range synthetic polymers with massively different qualities. They look different, they act different and  the general application of the term plastic to all plastic materials soon leads to confusion. Products such as varnish for example are not usually thought of as plastic. But some are.

But are all these different products basically made from the same stuff? No, even the base material can be a different product.

Plastic was used to describe the early first plastics derived from cellulose which were biodegradable. Later the same name was given the oil derived product. This was  made in a very different way and did not biodegrade. It is now applied to corn starch plastic which is made differently again, from plant starch and is certified compostable.

To conclude;
plastics can be made in a variety of ways from a variety of materials; shale gas, oil, plants even chicken feathers;
different plastics have very different qualities.

Currently non- biodegradable, oil derived plastics are the most commonly used and so we tend to ascribe their qualities to all types of plastic.
Which is of course incorrect not least because  most oil derived plastics do not biodegrade and last for centuries possibly for ever, while there are other plastics that are truly compostable with a lifespan of months.

It is important to know your different plastic types and their massively varied characteristics.
The sheer versatility of plastics make this a big task.

Check out A List Of Plastics for information on the individual kinds of plastic.

Lets get to know plastic! Key Points

Despite being lumped under the one, all-embracing name, not all plastics are the same..

Non-biodegradable and biodegradable plastics
Some plastics are compostable, (they biodegrade within a certain amount of time). 
Most are not biodegradable and last if not for ever, for a very long time. Read  the Plastic Lifespan to find out why and how.

N.B. Plastics can be described as compostable, degradable and or biodegradable. Which may seem clear but can be misleading. Some “biodegradable plastics” are oil derived plastics with a degrading initiator added to make them fall apart (degrade) more  quickly. Unlike compostable plastics they don’t always break down into harmless substances and may leave behind a toxic residue. Read more here

Thermoplastics or Thermoset?
You might also hear plastic being described as a thermoplastics or thermoset plastic.
Thermoplastics can be heated and shaped many times.
Thermoset plastics can only be heated and shaped once.

Made from?
Plastic can be made from pretty much anything from oil to chicken feathers….

How is plastic made?

Plastics are  created from single units, monomers, combined in a variety of ways. This process is called polymerisation. This is why plastics are also called polymers. And you often find the word poly used in the name i.e. polystyrene.

Building Blocks – Polymers & Monomers

A polymer is a chain  ( poly= many, mer = part) of  single units called monomers. 
Natural polymers occur in nature and can be extracted. They include silk, wool, DNA, cellulose, starch and proteins.
Synthetic polymers such as plastic are made by scientists and engineers. They too are extracted from natural resources BUT…. though the base material may be a natural product such as oil, the polymers derived from it are not.
To make synthetic polymers, the monomors are joined together in new ways, using heat and/or pressure and sometimes a catalyst.
Different combination of monomors result in different products and there are hundreds of different kinds of plastic.
Read more here – monomers and polymers.

Definitions
Don’t know your PETS from your hamster. Think Polymer is a girl’s name? Check out this collection of definitions essential for understanding plastic!

What Is Plastic Made From?

Obviously given the different products, there is no one answer – it would depend on the plastic type.
Plastic can be made from just about anything but the two main feed materials are oil and plants (bioplastics)

Currently nearly all plastics (and we are talking millions of tons each year) are made from ethane.

Most ethane is derived from oil but it can also be got from coal, gas and plants.

Oil Derived Plastic  
.. are cheap, so cheap they can be used to make one use throwaway products like plates and nappies in huge amounts.

Most oil derived plastics are resistant to chemicals, microrganisms and water. They don’t rot. They last for centuries possibly forever. Find out why most plastics don’t biodegrade here.
More are being made everyday.

How are oil derived polymers are made? You can see the process here.

Bioplastics

Bioplastics or organic plastics are derived from renewable sources such as starch, vegetable oil and even chicken feathers.

Some bioplastics are compostable and biodegradable. SOME ARE NOT.

For example:

Bioplastics can be made from ethane derived from plants. This is the same as ethane derived from oil. Both are  used to make PET plastic. PET plastic does not biodegrade.

PLA  is a  plastic derived from poly lactic acid that is a certified compostable plastic.

Different processes are used to make the various types of bioplastic. You can find links to technical information here. 

Plastic Types

There are thousands of different types of plastic product with different qualities. Some of those differences are down to the polymers, a lot are a result of later addatives.

The first stage in plastic production is the polymerization of raw material. Then substances such as fillers and chemicals are added to give color, texture and a whole range of other qualities. Reinforcing fibers for example make the base polymer stronger while man-made organic chemicals, such as phthalates are added to make plastic flexible, resilient and easier to handle.

While the polymers used in base plastics are considered harmless, the potential toxicity of the many additives is often unknown and some are thought to be dangerous. 

Find out more about additives fillers and plasticizers here.

Plastic Lifespan
Perhaps the most amazing thing about most plastics is that they don’t rot. While every other thing on the planet is decomposing, plastic remains unchanged. Find out why most plastics don’t biodegrade here.

A List Of Plastics 

The most common types of plastics, what they are used for and links to technical data sheets.

Bad Plastic

Problems with plastic Whats not to like?

Interesting  Check out this  great post by Chris Woodford

List Of Links


Quick Plastic Facts
List Of Plastics
 
 – the most common types of plastics, what they are used for and links to technical data sheets.
Plastic Lifespan why most plastic don’t biodegrade
Compostable plastics that biodegrade within a certain amount of time).
Compostable, degradable and or biodegradable plastic – find out here.
Thermoplastics and thermoset plastics – plastics that melt & plastics that don’t
Making Plastics
monomers and polymers
Oil Derived polymers  – how they are  made  see the process here.
Bio Plastics derived from plants see the process here 
Additives – Fillers and chemicals are added to the base plastic to give color, texture and other qualities.  Read up on them here
Reports & statistics  links to the latest reports on plastic

Blog INDEX

Welcome a quick introduction to everything
About Plastic  everything you need to know about plastic and somethings you wish you didn’t
Bad Plastic – why you need to cut your plastic consumption
Cut plastic – how to cut unnecessary plastic out of your life & meet the other people doing it.
Links & Projects –links to other plastic free people, the U.K. directory and out other projects
Us & The Boycott –About us the blog and the boycott rules
Site Map