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Can any plastic soda bottles be recycled back into their original containers? Is this at a rate of 25% or 50% or higher.

PET plastic beverage bottles can be – and are being – recycled back into beverage bottles.  (I don’t have data on the rate at which this is occurring.)  But not always.

The answer to your question has to do with how products made from plastics (bottles, bags, etc.) are collected for recycling and processed into raw material for reuse.

Plastic beverage bottles are collected, washed, shredded/chopped, melted and extruded to create new plastic pellets. These pellets (about the size of bb’s) are the basic raw material that companies buy to melt and shape into new products or packaging. These recycled plastic pellets are made available for sale to companies willing to pay the going rate for the material.

As you can see, this is where another class (economics) comes into play.

Bottles made into bottles is one option for recycled plastic – but not the only one. Let’s say, for example, the plastic bottle recycling facility is right next door to a plant that makes clothing. That clothing company may want to get its raw material (polyester plastic) from its neighbor to make t-shirts, in part because there are no shipping costs for the pellets.

In some cases, there may be extra costs involved to make sure the pellets can be used for certain things. For example, to turn plastic from a food or beverage container into another food and beverage container, it would be important to make sure that the plastic has been sanitized for the new use. This may mean that the plastic would need to be melted at a higher temperature. It may make more economic sense in this case to use the recycled plastic to make carpeting, for example, instead of bottles.

Do plastics decompose back into constituent elements or are they incapable of biological decomposition?

The biodegradability of plastics is an extremely intriguing area of research that is currently being investigated by many laboratories in academic and industrial settings around the world.

When considering if plastic is “biodegradable,” we must first take into account what is meant by the word “plastic.”   Two types of plastic are commonly used in consumer goods: thermoplastics and thermosetting polymers.

Thermoplastics are plastics that melt at elevated temperatures and are then formed into usable shapes; examples include grocery bags, plastic bottles, and other consumer goods.  Typically, thermoplastics are composed of very long chains of carbon atoms and incorporate different trace chemicals that impart certain properties into the polymer.  These long carbon chains are difficult for microbes to eat as an energy source because carbon bonds are very strong atomic bonds.  However, thermoplastics can degrade in the presence of UV light, such as sunlight, or under certain chemical conditions.  Under “natural” conditions, thermoplastics will take a long time to degrade.  Despite the resistance to degradation, thermoplastics are easily recycled.

Thermoset plastics are different in that the polymer is formed from a reaction between two different types of molecules, creating long molecular chains.  Common examples include foam padding and insulation made from polyurethanes.  These types of plastics cannot be heated and reformed as they are “set” after the reaction takes place.  The polymer chains are comprised of various carbonyl bonds that are much easier for microbes to use as an energy source than carbon chains.  Eventually, the polymers can degrade into their initial components, such as alcohols, amines, and carboxylic acids.  That said, the ability of the thermoset polymer to biodegrade will depend greatly on the environmental conditions, trace constituents, and polymer composition.

I hope this answer helps. Thanks for your question!

Professor Plastic

what plastics /rubbers besides medical grade silicone are acceptable. currently used for mouth pieces

Thank you for your inquiry.  To find out what kind of plastic is used in a specific mouth guard or dental work, you may want to call the manufacturer or consult with your prescribing dentist or doctor.  A mouth guard is generally for sports/athletic protection or serves a medical/dental purpose, such as to prevent teeth grinding.  Some mouth guards, such as those used for protection in sports events, are made from a plastic called EVA (ethyl vinyl Acetate).  Soft “night guards” could be made from silicone or other plastics.  ASTM classifies athletic/sports mouth guards in three categories; this standard may provide additional useful information to you.  See ASTM F697-00, standard practice for care and use of athletic mouth protectors.

Thanks for your question!

Professor Plastic

CAN, NATURAL FIBERS AND A COMBINATION COMMINGLE 1-7 UNWASH POST CONSUME PLASTICS, BE COMBINE TO MAKE A RESIN?

Thanks for your inquiry.  A resin has a very specific technical meaning: any natural or synthetic organic compound consisting of a noncrystalline (amorphous) solid or viscous liquid substance or mixture.  Natural resins include sap from pine and fir trees.  Natural resins have a long history of use to make things such as turpentine, shellac, and lacquer.  The reason that plastics are called “resins” is historical: some of the first plastics invented were intended to replace or perform better than natural resins, so the name “resin” stuck with plastics.

Plastics such as polypropylene, polyethylene, and polystyrene, to name a few, are sometimes referred to as plastic resins.  A mixture of different kinds of plastics is generally not called a “resin.”

That said, sometimes various plastic resins are combined to make a different compound.  Thermoplastics – that is, plastics that are defined in part by being able to be heated and reformed again – can sometimes be recycled together.

It also can be possible to introduce other things into a plastic resin to make it perform differently.  For example, “carbon fiber reinforced plastic” is actually a kind of plastic into which carbon fibers have been placed, giving the finished material greater strength.  Some companies that make decking from recycled plastics also add wood fiber, making what is called a composite deck.  In other cases, plastics are added to a natural fiber; some cotton jeans, for example, have a little bit of Spandex (a kind of plastic) added to the cotton fibers to add stretch.

Thanks for your question!

Professor Plastic

how much should i get for recycling translucent plastic? im in california

Thank you for your inquiry.  Professor Plastic is sponsored by a non-profit trade association and cannot provide specific information about the spot market for recycled materials.  If you are a recycler, you may wish to visit www.plasticsmarkets.org or recycleyourplastics.org for more information.

Thanks for your question!

Professor Plastic

I am interested in recycling HDPE at my home for some experimentation. My goal is to create a strong 1/2 inch thick tile. I have looked into pour-in surface molds, but get the impression if I melt cleaned chopped up pieces and heat to a pourable liquid that the end product is very brittle. What would be the best way to go about creating a strong reusable end product? Is there an additive or stabilizer that must be added?

Thanks for your inquiry.  Your project sounds really interesting.  That said, the melting point of HDPE is 266 degrees F, so your project is suited for an appropriate laboratory or industrial setting where there is proper equipment available.  In addition, melting or burning plastic at these (relatively low) temperatures could create fumes, so again, a lab or industrial setting with appropriate personal protective equipment and ventilation may be wise.

You might also consult the manufacturer of the packaging about whether your proposed home project is considered appropriate or wise.  Consumer products, including packaging, should be used in accordance with manufacturer’s instructions.

Another route you might want to consider is contacting companies in your area that are using HDPE as a raw material for more information … or discuss whether they might want to sponsor your project in their facility.

Thanks for your question!

Professor Plastic

Can the plastic CD cases be recycled

Plastic compact disc cases (usually called jewel boxes) typically are made with polystyrene plastic.  Polystyrene is a very versatile plastic that also is used to make automobile parts, furniture, foam protective packaging, foodservice products (cups, plates, cutlery, etc.), toys and more.

There are two ways to answer your question.  First – does the technology exist to recycle polystyrene?  Yes — polystyrene can be recycled into “new” polystyrene.  Second — are CD cases actually being recycled?  Again, yes — although it’s uncommon to collect CD cases in curbside recycling programs, there are many programs that accept them for recycling.  Check out Earth-911 [http://earth911.com/recycling/mail-back-programs-recycling-from-home/] for some of these recycling programs.

Did you know the CD itself is made with polycarbonate plastic?  Some of the same programs that accept polystyrene jewel boxes also accept the polycarbonate CD for recycling.

Thanks for your question!

Professor Plastic

Dear Prof. Why do we have issues with a sliding assembly using and Hd-PE and MD-PE (60/40)? I thought they were different enough not to cause any issues. Why do insiders say do not match to of the exact same resins for a sliding/friction application? Thanks a lot for your help

While I don’t know enough about the specific resins you’re using for your assembly, I believe that identical resins would have a propensity for cohesion: the tendency of similar materials to cling together. Probably not useful for sliding applications. Your best bet may be to check with a technical advisor from your resin supplier/s.

Thanks for your question,
Professor Plastic

Is polypropylene strapping that is composed of 97% Polypropylene, 2% chalk, and 1% dye considered a #5 plastic? I want to recycle this but am having a hard time finding information on it. Thanks!

Interesting question, specifically since you ask if the strapping is “considered a #5 plastic.”  It may be worthwhile to review information on the resin identification code which likely is the source of your “#5 plastic” reference.  It’s really important to note: the resin identification code ”was not intended to be — nor was it ever promoted as — a guarantee to consumers that a given item bearing the code will be accepted for recycling in their community,” according the organization that introduced the code in 1998.

In addition, the feasibility of recycling any product — an aluminum can, a newspaper, a plastic container — is dependent on many factors, such as local collection facilities, markets for the collected materials, transportation costs and more.  If you’re interested in determining whether you can recycle these products, perhaps you could start at www.plasticsmarkets.org which “connects suppliers and buyers of all types of scrap plastics.”  Hope this helps …  best of luck.

Thanks for your question,
Professor Plastic

How can I remove melted plastic from plexiglas, on a large scale? The protective plastic covering melted onto the plexiglass.

Wow.  This question is outside the realm of an academician like me.  Perhaps your best bet is to check with the manufacturer.  Wish I could be of more help…

Thanks for your question,
Professor Plastic

Is it economically feasible to recycle vinyl pools and other sheet vinyl products?

The feasibility of recycling any product — an aluminum can, a newspaper, a plastic container — is dependent on many factors, such as local collection facilities, markets for the collected materials, transportation costs and more.  If you’re interested in determining whether you can recycle these products, perhaps you could start at www.plasticsmarkets.org which “connects suppliers and buyers of all types of scrap plastics.”  Hope this helps … best of luck.

Thanks for your question,
Professor Plastic

How much electricity is spent when molding plastic to manufacture a single chair?

Hmmm …I guess that would depend on the chair, the manufacturing facility, the electric utility and many, many other factors.  This question may be better suited to the manufacturer of the chair in question.  Hope you find what you’re looking for … best of luck to you.

Thanks for your question,
Professor Plastic

I need to buy a roll of diamond shaped plastic 20′ X 40′ Like the kind they wrap Christmas trees in. It is to wrap outdoor items. I have no idea if it is sold that large or where to buy it. If you can help with this, please let me know. TY Sandra

Wish I could help, but unfortunately I cannot comment on matters regarding purchasing plastic products.  Hope you find what you’re looking for … best of luck to you.

Thanks for your question,
Professor Plastic

Where do I find start up money to start a plastic recycling company in Michigan?

As a professor and academician, I unfortunately am not in a position to answer questions about capital sources for businesses. That could jeopardize my tenure!  Perhaps your state development agency or your professional network can help with this question.  Wish I could be of more help … Best of luck to you.

Thanks for your question,
Professor Plastic

Is it more expensive to recycle plastic than it is to manufacture it from raw materials?

Like any manufacturing business, it depends. Manufacturing expenses are dependent on many factors, from transportation to local labor to raw material costs. When recycling plastics, the raw materials come from different sources than traditional manufacturing (such as community recycling programs rather than chemical facilities) and often use different manufacturing techniques. Add in other factors — how far are the used plastics shipped?  What about local labor costs? — and the answer is: it depends.

To find out more about plastics recycling, click here.  http://plasticsmakeitpossible.com/category/living-green/recycling-reusing/

Thanks for your question,

Professor Plastic

I want to make come black plastic dowel about 1/8 dia. 1 inch long where do I buy the plastic?

As a professor and academician, I unfortunately am not in a position to recommend specific plastic products or commercial suppliers of plastics.  That could jeopardize my tenure!  Perhaps your existing suppliers or your professional network can help with this question.  Wish I could be of more help … Best of luck to you.

Thanks for your question,
Professor Plastic

How is plastic used in fabric and fashion?

A lot of designers are incorporating recycled plastics into their collections and products. For more information on plastics and fashion, click here for info on recycled plastic fabrics http://bit.ly/qEXWgP, check out our Plastics In Your Life fashion page http://bit.ly/nlz8zB, and watch George Kotsiopoulos’ video on plastics and exercise fashion http://bit.ly/p7A5Xz.

Thanks for your question,
Professor Plastic

What are five consumer products that are made out of recycled plastic?

More and more brands are now offering products made from recycled plastics. Here are just a few examples of some:

Carpeting: http://bit.ly/n1yJ2U

Decking:  http://bit.ly/qJdlPG

Phones:  http://bit.ly/qeEpI6

Purses: http://bit.ly/ol7i15

Car interiors:  http://bit.ly/rthXi3

Thanks for your question,
Professor Plastic

What can be made out of recycled plastic bags?

Lots of things, including durable building and construction products – door and window frames, exterior moldings, low-maintenance fencing and decks, and more. Here is some info on recycling plastic bags from Earth911: http://bit.ly/nSXSJZ

Thanks for your question,
Professor Plastic

What does the number in a triangle at the bottom of plastic containers stand for?

Great question! This is often an area of confusion for most consumers. That little symbol on a plastic product identifies the type of plastic (resin) used to make that item. Click here for more info:  http://bit.ly/o9ENJ8 

Thanks for your question,
Professor Plastic

We are looking for a foodgrade plastic that can be thermoformed and can withstand 350 degrees of heat to manufacture hard candy molds. Help!!

As a professor and academician, I unfortunately am not in a position to recommend specific plastic products or commercial suppliers of plastics.  That could jeopardize my tenure!  Perhaps your existing suppliers or your professional network can help with this question.  Wish I could be of more help … Best of luck to you.

Thanks for your question,
Professor Plastic

What Things Are Made from Recycled Plastic?

So many things! From American flags (http://bit.ly/pEcLvU) to carpeting (http://bit.ly/n8GIbr), decking (http://bit.ly/r3Eq67), purses (http://bit.ly/p7JIrT), auto interiors (http://bit.ly/qs9xvj), and cell phones (http://bit.ly/mVyNdm), more and more brands are offering products made from recycled plastic. Did you know that more than 80% of Americans say they feel more “green” when they buy products for the home that are made from recycled plastics? (http://bit.ly/qNPDpa)

Thanks for your question,
Professor Plastic

What are some great examples of reuse fashion design?

Many designers are incorporating recycled and reused materials – including shopping bags, wine glasses, and candy wrappers – into their designs. Check out some of the ways that reused and recycled plastics are making their way into the world of fashion: http://bit.ly/oTwoBd

Thanks for your question,
Professor Plastic

What are the ’4 Rs’ of sustainable living?

Reduce, reuse, recycle and rebuy! Have you had a chance to check out our Recycling and Reusing center? http://bit.ly/r0hEow  We have lots of ideas on how to recycle and reuse more of the plastics you use everyday. Remember – plastics are too valuable to waste. Reuse and recycle!

Thanks for your question,
Professor Plastic