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Borosilicate Glass is a specialized form of glass that uses boric acid as a component in its fabrication. The result of the addition of the element boron is a type of glass that is very resistant to thermal shock and exhibits a much lower coefficient of thermal expansion than that of common silicate glass. In this article, a review of borosilicate glass will be presented, including its development, properties, and uses.

Development of Borosilicate Glass

Back in 1882, a German chemist named Otto Schott was interested in experimenting with ways to create glass that had the ability to withstand sudden changes in temperature or exposure to uneven temperatures without shattering. In that year, he made the discovery that ushered in the creation of the Borosilicate Glass Tube. Schott discovered that the addition of the element Boron to the glass fabrication process resulted in a heat-resistant form of glass.

Later work by chemists W.C. Taylor and Eugene Sullivan at Corning Glass refined the efforts of Otto Schott and expanded the temperature resistant properties of borosilicate glass. As a result of these innovations, customized glass fabrication grew, where there is now over a million different formulations of glass that can be customized for specific product needs by enhancing the desired physical and mechanical properties of glass.

Perhaps the most well-known application for borosilicate glass grew from further research at Corning Glass. After joining the company in 1914, physicist Jesse Littleton was given the task of testing and evaluating the physical properties of the newly created glass formulation. After his wife’s ceramic casserole dish accidentally broke, she suggested that perhaps this newly developed heat resistant glass might prove to be a useful product for baking. After she tested the notion by baking a cake in a sample glass container that Littleton had brought home, a new use for Borosilicate Glass Rod was born – glass cookware. Corning Glass introduced a line of products known as Pyrex®, which was for many years of its manufacturing run produced using borosilicate glass.

Properties of Borosilicate Glass

Borosilicate glass is generally chemically resistant, but perhaps its most remarkable physical property is its low coefficient of thermal expansion, which explains why the glass can resist shattering under sudden rapid changes in temperature. Glass generally is a poor conductor of heat, so when you take hot glass and immerse it in cold water, the exterior of the glass cools rapidly while the interior does not. The stresses caused by the temperature differential cause the glass to shatter.

With Borosilicate Glass Solar Vacuum Tube, the addition of boric acid (H3BO3) to the formulation results in a glass that has a low coefficient of thermal expansion, which means that when the glass is heated or cooled, it does not expand or contract very much. This dimensional stability is what enables borosilicate glass to be capable of withstanding rapid and extreme temperature changes without cracking.

The chemical composition of borosilicate glass typically consists of around 81% silicon dioxide (SiO2) and 13% boron trioxide (B2O3) with lesser concentrations of sodium oxide and aluminum oxide. (Note that the concentrations of boric oxide can vary, 5-13% is typical). The element Boron is what provides the glass with its dimensional stability so that the material doesn’t shrink or grow as the temperature to which it is exposed changes.

Applications of Borosilicate Glass

The initial problem that was attempting to be solved at the time that Otto Schott began experimenting with glass formulations was to create a glass that could stand up against extreme temperature exposure. For example, the glass that was used in lanterns at that time would end up shattering or cracking in rainy conditions because the cold rain on the exterior surface of the glass caused a large temperature gradient when compared with the temperature of the hot interior face.

Plastic can be a problem. It might seem strange for a company called “Plastic Place” to acknowledge such a thing, but it is absolutely true. While the invention of plastic has done a massive amount for humanity, revolutionizing everything from sanitation to health care, no technological advance comes without its price. Improperly discarded plastic is one of the most urgent problems facing the environment today. According to the U.S. Environmental Agency, only 8% of the 31 million tons of plastic waste produced each year is recycled. Much of the rest ends up as litter and pollution, clogging waterways, threatening wildlife, and releasing potentially toxic chemicals into the earth. Being so aware of this conflict is what drives our commitment to finding greener ways of dealing with trash, especially when it comes to the production and disposal of plastic bags.

When Biodegradable Garbage Bags first arrived on the scene, they were hailed as the scientific breakthrough that would cure all the problems that plastic can create. The idea of a plastic that would behave and break down just like a natural material seemed too good to be true. Was it? We took a look at the facts and found out.

What does “biodegradable” actually mean?

First it will help to define the sometimes confusing terms which are often used interchangeably when discussing biodegradable plastics.

“Regular” plastic is a synthetic material created from petrochemicals. Without getting too deep into the science, the long polymer chains in regular plastic are so resilient and resistant to breakdown that they can last for hundreds of years.

Biodegradable Clothes Bags, which are also made from petrochemicals, are manufactured differently so that they can begin to break down quickly in the presence of air and sunshine. You might see this plastic labeled as photodegradable or oxy degradable.

Bioplastic is made from organic, renewable sources, such as vegetable oils, corn, and grains.

Compostable plastic, which is usually bioplastic, doesn’t just break down: as it decomposes, it will create humus, which adds valuable nutrients to the soil.

One of the first problems with “biodegradable plastic” was that in the early days there was no consensus on what qualified as biodegradable. Dubious claims abounded as companies rushed to get on the green bandwagon and made all kind of promises to consumers that were not actually true. Eventually, the Federal Trade Commission stepped in with a strict set of guidelines defining exactly what could and could not be labeled as biodegradable.

The limitations of biodegradable plastic

“Returning to nature” is a pretty poetic idea, but is that actually what happens when Biodegradable Pet Poop Bags arrive at the landfill? The problem with the FTC guidelines is that some extremely important factors are completely left out.

First of all, the “reasonably short period of time” is not defined. It could mean any amount of time from a week to several years.

Next, and most importantly, there’s no discussion of the type of environment required for this breakdown to occur. The fact is that most plastic ends up in landfills. Canada’s Environment and Plastics Industry Council (EPIC) estimates that even though two thirds of the plastic in a landfill could be called biodegradable, once it reaches that dry and airtight environment, it pretty much halts the biodegradation process, and the plastic just sits there along with its non-biodegradable counterparts. By design, the conditions in a landfill are extremely hostile to the biodegrading process. Nothing is actually meant to decompose there: air, moisture, and sunlight, the three factors most necessary to decomposition, are purposely kept out of landfills in order to cut down on greenhouse gas emissions. This means that even if Biodegradable Roll Draw Tape Bag did break down in this environment, the consequences would be far from rosy. As it degrades, it releases two greenhouse gasses: methane and carbon dioxide, which both contribute hugely to global warming. Many traditional petrochemical-based biodegradable plastics also leave behind toxic metals and traces which can contribute to soil and water pollution.

As if that wasn’t enough, consider this: biodegradable plastic cannot be recycled with other plastics.

Biodegradable plastic is marked “7” while most other recyclable plastics are a “1” or a “2”. If bioplastic is mixed in with these, it will contaminate the whole batch. You don’t need to be an environmental scientist to know that’s not a good outcome.

Finally, even relatively friendly bioplastics have their drawbacks: arguably, the land and resources and carbon output used to grow corn and other materials for bioplastic might be better used growing actual food. The genetically modified crops used for the production of bioplastic and the necessary chemical fertilizer and pesticides have their own consequences for the environment. On a very practical level, these Biodegradable Loop Die Cut Handle Bags are often not as strong as petrochemical-based bags, which means that they may require double-bagging. Using more plastic instead of less isn’t a sustainable solution.

What biodegradable plastics can actually do for the earth

Truly compostable bags can also make a big difference. If your city offers a commercial composting facility, using these Biodegradable Mailing Bags for your food and yard waste is a great option which may encourage more composting: a pure win for the environment. For do-it-yourselfers with a backyard compost bin, some bags are also suitable for home-composting, but check the label carefully.

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