San Bernardino Plastic Delrin

The fundamental science behind stretch blow molded polyethylene terephthalate (PET) has advanced considerably in its quarter-century history. Throughout San Bernardino and the surrounding areas, the use of clear PET water bottles has grown significantly. We now have a far better understanding of the particulars involved in the successful production of PET containers, which display excellent performance at commercially feasible costs.

More than two decades have passed since the first stretch blow molded polyethylene terephthalate (PET) container was made. In filling the demand for inexpensive, high-performance, resealable containers to package food, personal care, and other products, biaxially oriented PET, in particular, has won great acceptance from consumers.

Bottle Grade PET

When all other considerations are equal, a container with a unique proprietary shape offers more in the way of shelf appeal than one with a plain appearance. However, uniquely shaped containers, as attractive as they may be and as popular as they are in San Bernardino, can sometimes compromise other interests of the consumer or manufacturer. Such shapes often have variable contours that may evoke geometric yielding under lower carbonation levels and lower external forces, or cross sections that deviate from a circular geometry and create additional surface area. For instance, a bottle with a square cross section has 1.128 times the surface area of a bottle with a circular cross section, assuming equal volume and height.

The introduction of additional surface area, without an increase in bottle mass, results in lower wall thickness per unit volume, ultimately inducing carbonation loss. It is important to learn about plastic and materials used in our everyday products. Moreover, undesirable material distribution and nonuniform orientation are a consequence of complicating the stretch blow process. This only magnifies the detrimental effects on the container’s physical properties.

Plastics!, Marketing Methods Article

Acetal Plastic Sheet

A Serious Environmental Problem

Plastic waste is a very serious and rapidly growing environmental problem. Our love of plastic items and our careless disposal of these items when they're no longer useful is polluting land and water, endangering wildlife, and creating eyesores that are changing the face of the Earth.

Another tragic situation on Earth is the widespread existence of poverty. Some people have inadequate shelter or no shelter at all, a lack of safe or sufficient drinking water, or insufficient food. In some cases people experience all three of these problems. Another frequent symptom of poverty is lack of education.

What if the dual problems of plastic pollution and poverty could be dealt with at the same time? This is the aim of an organization called the Plastic Bank. The organization encourages people to "harvest" plastic waste and deliver it to collection or repurposing centres. In exchange for the waste, the bank gives the harvesters money, services, or useful items. The harvesters can either use the items that they receive or sell them. The bank hopes to both help people directly and to encourage entrepreneurship.

The Plastic Bank recycles the harvested material into pellets, which can be used by manufacturing companies. The bank calls their product social plastic. One of its goals is for all plastic items to be made of this material.

The Founders of the Plastic Bank

David Katz is both a businessman who travels extensively and a scuba diver. In his travels he's been struck by the amount of plastic waste around the world. He says that he decided to create the Plastic Bank after he visited Malaysia and found a beach which appeared to have more plastic than sand.

Katz has formed a partnership with Shaun Frankson, another businessman and the co-founder of the bank. The pair want to monetize plastic debris, enabling it to become a currency. In their view, discarded plastic is a valuable commodity that is being wasted. The pair also want their business to be philanthropic.

Using Social Plastic to Help People

A Plastic Bank collection centre accepts any type of plastic. The collectors don't have to classify what they find. The centre gives the collectors credits in return for their harvest. The credits can be used to obtain goods or services. The nature of these goods and services will depend on the needs of the people in the area. Examples include items such as tools, household items, and parts, and services such as education and micro-credit loans.

Some collection centres are also repurposing centres that use harvested plastic to create filament for 3D printers. People can order printed objects in exchange for the plastic that they collect.

In the interview with Shaun Frankson shown below, Frankson says that the bank avoids paying harvesters cash for their plastic because money becomes "very corrupt very quickly". The organization seems to have changed its opinion since the video was made, however. It's currently giving people money for their harvest, at least in Haiti.

Katz and Frankson are helped by plastics recycling experts, business people, philanthropists, and environmentalists. They are also aided by people who will explore local needs and recycling opportunities, publicize the bank's efforts, and perform impact studies after a collection centre has been established.

Plastic Waste in the Ocean

More than 300 million tons of plastic is said to be manufactured each year. More than eight million tons (or ten to twelve million tons by some estimates) is said to enter the ocean each year. Much of this plastic stays in existence for a very long time once it's made. Plastic does degrade in the ocean, but it disintegrates very slowly.

Aquatic animals become entangled in pieces of plastic and sometimes mistake them for food. Another problem is that the degradation of plastic produces small particles of microplastic, which enter the food chain and are absorbed by living things. Researchers have found that microplastic is present in supermarket fish and shellfish, which means that it enters our body when we eat these foods.

Scientists don't yet know how microplastic is affecting us or even if it is, but the situation is worrying. Microplastic particles are known to absorb harmful contaminants such as pesticides, flame retardants, and PCBs (polychlorinated biphenyls). If they hurt us, they will likely affect the animals that absorb them as well.

Recycling Plastic Waste

Recycling of plastic is certainly very necessary. One problem with processing the material is that there are many different kinds of plastic that each require a different treatment. Sorting the material by type is vital before any recycling can be done.

At least at one time, one of Katz's team was Mike Biddle, as mentioned in the video above. Biddle is a co-founder of a company called MBA Polymers. This company carries out the automated sorting of plastic. Its recycling centres are located in several countries and process one million pounds of plastic a day. This is apparently only a fraction of the material that collects on a daily basis. Biddle estimates that only about ten percent of our daily buildup of plastic waste is recycled. According to him, recycled plastic is pound-for-pound more valuable than steel.

Biddle would like the word "consumer" to be eliminated in relation to plastic. He believes that all plastic products should have once existed as a different product. One of his goals, which is also a goal of the Plastic Bank, is to change people's attitudes. People need to think that plastic is too valuable to leave on the ground or in the water.

Collection and Repurposing Centres

The founder of PeruRail provided land and financial support for the first Plastic Bank collection centre in 2014. Peru was an appropriate place for the project to begin. According to David Katz, only 2% of that country's waste stream is recycled. Much of the discarded plastic and other waste enters the waterways.

The Plastic Bank also has collection centres in Haiti, which like Peru has a serious problem with plastic in waterways. Here collectors can deliver their plastic to solar powered centres in order to receive money, items, or services such as sustainable cooking oil, soap, wifi access, or a charge for their phone. The bank is also operating in the Philippines and plans to begin operation in Indonesia and Brazil soon.

It will be interesting to watch the evolution of 3D printer use in the repurposing centres. 3D printers are certainly becoming very capable and their cost is decreasing rapidly. Many of them use plastic as a printing medium, so the printers would seem to be well suited for the recycling of plastic.

One question that needs to be answered is whether repurposing plastic from one use to another will actually reduce the amount of plastic waste or simply maintain it at the current level. This is something that needs to be closely monitored in any recycling effort.

Reducing Poverty

The Plastic Bank sounds like an excellent plan in principle, but time will tell whether it works in practice. I very much hope that the bank is successful and that if there are any problems the system is modified to solve them. So far the project seems to be progressing well.

The serious global problems of plastic pollution and poverty each need an effective solution (or more likely, many different solutions). Hopefully the Plastic Bank will help to reduce plastic waste and decrease the incidence of poverty, as it is intended to do.

References and Further Information

  • The plastic bank has a website at
  • The organization also operates a website at Both sites have social media accounts.
  • Scientists were interviewed for a CBC (Canadian Broadcasting Corporation) article about microplastics in supermarket fish.