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Coatings & Surface Engineering

The Coatings & Surface Engineering is the place for conversation and discussion about coatings; substrate modifications; cleaning and surface preparation; and friction, lubrication and wear. Here, you'll find everything from application ideas, to news and industry trends, to hot topics and cutting edge innovations.

Water Bottle Materials (Part 2) - The Plastic Alternatives

Posted October 03, 2012 12:00 AM by cheme_wordsmithy

I may just be spit-balling here, but I'm guessing a lot of people don't drink as much water as they should. Enter the reusable water bottle - a great way to both save the environment, your wallet, or a few trips to the water fountain everyday while getting the fluids you need.

But what type of water bottle is best? As far as utility goes, plastic seems like a no-brainer (at least in my book). It's lightweight, durable, tasteless, easy to clean, (often) transparent, and more insulate (heat resistant) than metal. But we live in an imperfect world; chemical leaching and the BPA scare have deemed many plastics to be (skeptically) "unsafe". So what's a health-concerned person to do who wants a reusable bottle for their water (or Powerade/Gatorade, apple juice, goat milk, whatever floats your boat…)?

Well, back when I was searching for the right water bottle for myself a few weeks ago, I did a little research on other water bottle options besides injection molded plastics. The three realistic alternatives are stainless steel, aluminum, and glass. Let's take a quick look at each:

Stainless Steel

Stainless steel is steel alloyed with chromium (in a minimum amount of 10.5% by mass) to make it much more corrosion resistant. Stainless steel reusable water bottles are typically made from 18/8 alloy, meaning 18% chromium and 8% nickel. Unlike many other metals and materials, stainless steel does not leach any chemicals and has minimal problems with rusting or staining when in contact with water. Stainless steel bottles often have plastic (typically polypropylene) tops so you don't taste the metal or hurt your teeth if you hit a bump while drinking. Stainless steel is also very durable, lightweight, and easy to clean, making it ideal for hikers and office workers alike. However, it is metal, which means a few things: first, it heats up a lot faster than plastic. Second, it is still susceptible to some rusting and staining (especially low-quality stainless steel, though this can usually be cleaned off with a brush and good washing). Third, it makes a loud clanging sound when it hits things (I know, minor detail, but it is something).

NOTE: This clanging feature can also be used as a surefire way to annoy your hiking partner, should you position the bottle to make noise with ever motion of your pack…

OK, now that that's cleared up, onto aluminum…

Aluminum

Aluminum is a hard, lightweight metal that most people are familiar with in various forms, from aluminum foil to beverage cans to the framework of cars and bicycles. Aluminum bottles have similar properties to stainless steel bottles, both being metal. One benefit of aluminum is that it is lighter weight than stainless. However, aluminum is less durable than stainless steel and is also a better conductor; thus it transfers heat (cools and heats up) faster. Also, because aluminum suffers from leaching, bottles are coated with a special lining to separate and protect the aluminum from the water. Because of the possibility of breaking this lining through wear or scratching, some attest that stainless steel is "safer" to use than aluminum. Aluminum bottles are also more expensive than their stainless competitors, but some designs do (arguably) look cooler.

Glass

Glass is an amorphous solid composed largely (~75% by mass) of silica (SiO2), along with some other metal oxides such as Na2O and CaO. Glass has a much longer history than other modern materials as a beverage container. It is superior to metals and plastics in that it does not suffer from any leaching, rusting, or staining problems, and exhibits (in my opinion) the best drinking taste of all beverage materials. Oh, if only I had lived in the era of the glass Coca Cola bottle... *Sigh* Unfortunately, glass has two major flaws: it's heavy and it breaks. So you can forget about glass if you're planning on doing a lot of hiking or travelling, unless of course you feel like lugging the extra weight and don't mind having a razor sharp mess looming in your future. Conveniently, many glass water bottles are now made with silicone/rubber sleeves for added protection and grip, making glass more practical for everyday use.

Conclusion

For the hiker in me, I prefer stainless steel to aluminum or glass for its durability, cost, and chemical "safeness". Besides the weight factor (and let's face it, the water takes up most of the weight anyway), I just don't see much benefit of aluminum over stainless steel, especially considering its higher cost and the factor of the added coating. And while glass bottles are cool, I can't won't use them for hiking, so I don't see the point of owning one on top of the stainless or plastic bottle I already have.

I'm curious to hear your thoughts. Has the water bottle material dilemma ever crossed your mind?

Aluminum Bottle Image

Glass Bottle Image

Stainless Steel Bottle Image

3 comments; last comment on 10/04/2012
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Water Bottle Materials (Part 1) - Plastics and BPA

Posted September 26, 2012 12:00 AM by cheme_wordsmithy

Stirred by the Hike

Recently I've been doing a lot of hiking up in the Adirondack High Peaks region. The climbs and views are spectacular, and the workout itself can't be beat. The longest (and most recent) hike I did was a 14-mile round- trip over Nippletop Mt. and Dial Mt. Some of the highlights included a beautiful waterfall, a quaint little pond, a young and developing forest of saplings, a nice landscape view from the top of Dial, and a torrential downpour over the last two miles of trail. It was pretty great.

All this to say, I typically use a 100 oz (~3 liter) bladder pack to carry the majority of my water. Though I ended up having plenty, I decided I would also bring an additional 1 liter Nalgene with me as well on the 14 miler. It was an old water bottle, one I had dug up from my parent's place a month or so beforehand. A few days after the hike, I was reminded somewhere about the plastic scare that drove Nalgene and other plastic companies to make their bottles out of new materials. When I checked my own, I found them to be type 7 polycarbonate plastic; plastic which I knew consisted of the infamous BPA.

BPA - Bad Boy or Bad Hype?

Bisphenol-A (shown right), or BPA as it is commonly called, is an organic solid used to make polycarbonate polymers. BPA has had quite a history since 2008, when some government agencies became skeptical about its health safety. In the wake of certain studies and research, the chemical was said to be linked to a number of health problems stemming from its identity as a weak endocrine disruptor (simply put, a chemical that messes with hormones). Its properties are said to mimic those of estrogen, and alarming concerns have been raised about its effects on fetuses, infants, and children.

Many European and U.S. administrations, including the US Food and Drug Administration, European Food Safety Authority, and Environment Protection Agency (EPA), say that current levels of BPA pose no threat to most people. Studies by The Endocrine Society say otherwise, and have led to the ban of BPA in baby bottles and many plastic water bottles.

(<-- Credit: Productwiki Inc.)

I really have mixed feelings about the whole BPA hype. A study conducted by the EPA said it had concluded that the bodies of healthy adults rapidly process and eliminate BPA, so that it isn't a concern. However, anything that says it can mess with hormones sounds fishy to me, so I took the "better safe than sorry" approach. I bought a replacement bottle advertised as "BPA free", so I can use it guilt-free at work and on hikes in the future.

Plastics - They All Leach

Truthfully there are no completely "safe" plastics out there. Due to the nature of the plastic making process, which typically involves many steps and additives, there's good reason to believe that most plastic products leach chemicals at some level. The biggest concerns are from those chemicals that, like BPA, are characterized by "estrogenic activity". Unfortunately, a study in Environmental Health Perspectives found that most plastic products (even BPA free ones) do contain other chemical compounds which mimic estrogen. Alas, perhaps my BPA-free quest was in vain… at least I got a new water bottle out of it.

Seriously though, until more studies are done on the effects of these substances in humans (most have been done on rats and mice), it's hard to say anything conclusive one way or another. CR4ers, I would love to hear your opinions on this subject. Right now, I plan on following the old advice to avoid subjecting my water bottles to dishwashers and microwaves, as extreme temperatures and abrasion are known to exacerbate chemical leaching in plastics.

(Credit: Buy.com Inc. -->)

Of course, if you're looking to go completely plastic free, there are a few good material alternatives to reusable plastic water bottles. More on that in my next post.

References

Bisphenol A - Wikipedia

Study: Most Plastics Leach Hormone-Like Chemicals

10 comments; last comment on 09/27/2012
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The Real 2012 Election: Oil vs. Latex Paints

Posted August 16, 2012 9:32 AM by HUSH

Note: This is NOT a blog promoting a political agenda. All allusions to politics are purely for entertainment, so keep your non-paint opinions to yourself!

It's the debate that has lasted far too long, and puts friends and family at permanent odds. It has caused divorces, bankruptcies, and even fistfights amongst nuns.

What debate am I referring to? It's not the existential man vs. woman examination, the adorable puppies vs. babies argument, or the delicious burger vs. hot dog dispute. (Where do I stand on the issues this election season? Women; puppies; and burgers. Here here!)

Nope. It's latex vs. oil. Paint that is. Just paint, okay?

Yours truly knows his way around a roller tray, with sections on my resume including stints as a painter, as well as a paint salesman. Naturally I have a predisposition, but I'll offer my best non-partisan take to provide you--the voter--with the facts needed to make an educated choice.

No amount of buttons can stop me from delivering the facts!...via Freedom's Phoenix

Paint History

Last year, South African archeologists discovered the remnants of a paint-production process estimated to be 100,000 years old. Uncovering new rock layers in a cave already known to be an anthropological goldmine, researchers discovered seashells that had been dyed red from ocher, a clay that is red in color from naturally occurring hematite. The ocher and animals bones were ground and heated, releasing marrow. After adding some urine, cave-folks found they had a spreadable paste.

...via Freddy and Petunia

Paint has been used henceforth, from early stick figures and maps--to the Italian Renaissance--to discussing with your wife what color to paint the den. No, not white. How about artic white? Or off-white, or pure white, or cream white, or toned white, or…..

Painting: so easy a caveman can do it. Or a politician… *rimshot*


Binders (of Paints!)

The binder is the most important component of the paint, as it is responsible for the sheen level (flat, matte, eggshell, gloss, etc.), adhesion, and durability. While we can obviously rattle on for days about different binder types, let's keep this simple and keep the discussion between latex and oil. (See how I glazed right over voting alternatives? Just like two-party politics! Burrrrn!)

The Candidates: Oil and Latex

The first thing you notice about oil paint is the smell. It has a decidedly heavy odor, and good ventilation must be provided during application. Smell is decidedly in favor of latex paint; with a mild aroma it still requires ventilation. Preparation is higher in degree when working with oil paints, and thinning must be done with turpentine or mineral spirits. Latex only requires water.

"He's only smiling until he sees the divorce papers," she was reported as saying...via Shelby Paint

Whatever is being painted is obviously a consideration. Oil paints work best on metal, bare wood, and dirty surfaces. Latex paint, is a water-based film, so it swells wood grain and when dried, cannot offer the flexible coating desirable for metal surfaces. Oil also has a smoother, more finished appearance when dry. Oil-based paint also offers a higher degree of durability, though it has a shorter service life--it discolors and peels far quicker than latex. Latex paint dries about 85% faster than oil paints and it is perfect for non-traffic areas, including exteriors.

Oil paint and its associated solvents are toxic in nature, so government restrictions (aghhh!) apply to their disposal. Even long-cured latex paint is removable with just warm water and soap.

The Choice

Your vote depends largely upon your material, traffic needs, and skill level. Latex paint is perfect for the weekend DIYer, and even most professional painters use latex on prepared drywall and plaster.

I think P. Diddy may be taking this whole paint thing a little too far...via Huff Post

No matter your choice though, there is no right or wrong. It's about being a part of the democratic process! It's your CR4 civic duty!

Voice your vote in the responses below!

Resources

My brain

HG TV - Painting 101: Oil or Latex

Home Addition Plus: Oil Based Paint versus Latex Based Paint

Wikipedia - Paint

Live Science - Oldest Human Paint-Making Studio Discover in Cave

8 comments; last comment on 08/20/2012
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Got a "Million Dollar" Idea?

Posted January 24, 2012 9:58 AM

While some inventors do strike it rich, commercializing an idea is a long, complex process that requires time, money, and patience. Are you a do-it-yourselfer with a garage full of interesting contraptions or a notebook filled with sketches for the latest and greatest idea? Are you considering a patent for one of your ideas? What about marketing your product to a wider audience? Does your company have intellectual property rules that prohibit you from going it alone?

The preceding article is a "sneak peek" from Coatings & Surface Engineering, a newsletter from GlobalSpec. To stay up-to-date and informed on industry trends, products, and technologies, subscribe to Coatings & Surface Engineering today.

6 comments; last comment on 01/25/2012
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Can Green Coatings Become Food Friendly?

Posted January 06, 2012 7:00 AM

As food production processes become more automated, there is a need for food-grade coatings and lubricants to keep the machines running smoothly and the food safe for consumption. One company, Ecology Coatings, is filing a patent for "UV-curable products that can be used safely in direct contact with food for both humans and animals." Are green coatings now cornering the food-friendly market?

The preceding article is a "sneak peek" from Coatings & Surface Engineering, a newsletter from GlobalSpec. To stay up-to-date and informed on industry trends, products, and technologies, subscribe to Coatings & Surface Engineering today.

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Green Chemistry: From Pilot to Profit

Posted December 02, 2011 9:15 AM

Pike Research reports that the market for green chemistry is poised to grow from $2.8 billion in 2011 to $98.5 billion by 2020. While many companies are just now building pilot labs to test green products, they have their eyes on the immense chemical products market. Is your company investing in green chemistry, and if so, what industry sectors are you focused on?

The preceding article is a "sneak peek" from Coatings & Surface Engineering, a newsletter from GlobalSpec. To stay up-to-date and informed on industry trends, products, and technologies, subscribe to Coatings & Surface Engineering today.

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