For any reader who isn’t aware, most of the world’s plastic is currently made from crude oil. The process involves several steps, depending on the polymer that one is creating, but the total cost is still a fraction of the cost needed to create biopolymers of the same quality. Biopolymers are created by having a culture of bacteria consume large amounts of biomass. When the bacteria are mature, the culture is sterilized and the biopolymer is extracted directly. Many factors are now causing chemical and plastic companies to consider possible ways to reduce their reliance on crude oil, so reducing the cost of biopolymer production has become a greater priority. Since the polymer-using world cannot simply pay double or triple for things like plastic bags, plastic bottles, and plastic tubing, achieving this cost reduction is the missing critical factor to wide scale use of biopolymers.
The difference in cost between standard polymer production and biopolymer production is not caused by any one factor. Since the world uses such a large amount of plastic, existing polymer production facilities are huge, whereas biopolymers are mainly produced by small specialty groups and laboratories. Several companies are now considering the construction of large scale biopolymer factories, but they are waiting on the researchers to bring down the other areas of cost first. At present, it requires 3 times the weight in biomass to create a unit of biopolymer. This is because the bacteria being used are only able to consume certain nutrients from the biomass, leaving the rest behind as unusable waste material. Efforts are underway to find or engineer a more efficient bacteria for this task. The other side of the coin is to more effectively process the biomass such that a greater portion of it is consumable by the bacteria. Many different areas of research are currently being conducted toward this achieving this end, because labs and universities know the impact of these discoveries will be felt for centuries to come and the shorter-term breakthroughs could easily lead to a Nobel prize.
The Progress of Biopolymers
July 11th, 2010Understanding Radiopacifiers
May 17th, 2010In many custom tubing applications, it is desirable to manufacture the components such that they can be seen with fluoroscopy or x-ray imaging. Typically this is done by blending the polymer with another material, the radiopacifier, which is chosen because it has a higher radiopacity. With many different radiopacifiers available, it is useful to understand the strengths and weaknesses of each before making a selection.
Barium Sulfate(BaSO4) – Barium Sulfate is the most commonly used radiopacifier for almost all medical applications where imaging is an issue, including catheters and other types of tubing. While BaSO4 does not have the highest level of radiopacity, it remains moderately priced compared to the alternatives. Because it is not as dense as other radiopacifiers, a high volume of barium is needed to achieve a high level of radiopacity and typically the barium begins to affect the strength of the polymer after it exceeds 20% by volume. BaS04 also tends to mix more easily with elastomers than the other alternatives.
Bismuth(Bi) – Several different bismuth salts are commonly used as radiopacifiers, all of which have a higher density than Barium Sulfate. The high density creates a higher weight-to-volume ratio, which means that the resulting polymer can be more radiopaque with a lower volume percentage of the bismuth salt. While bismuth fillers have been growing in popularity, the fact that they are much more expensive than Barium Sulfate still precludes their use for certain applications.
Tungsten(W) – Tungsten is considerably more dense than the other alternatives, providing the highest weight-to-volume ratio of any commonly used radiopacifier. Because of this, polymers made with tungsten can be extremely radiopaque without a significant change in mechanical properties. Though raw tungsten is also relatively inexpensive, its other properties ultimately make it a more expensive choice for many applications:
1. Tungsten is highly flammable
2. Tungsten is black and extremely difficult to change the color of
3. Tungsten is abrasive, causing accelerated wear on processing equipment and surface roughness in the end result
Preserving Our History with 3D Printing
March 16th, 2010Beyond the manufacturing advantages, the combination of 3D scanning and 3D printing has led to an incredible way of preserving rare artifacts from the past. For many collectables, the primary reason they have dwindled in number has always been the extreme cost of having the original molds remade from scratch. With a 3D printer, the physical molds are replaced with digital instructions, provided by a 3D scan of the original object, or created carefully with design software. This process has been used to recreate tools, toys, machine parts, forgotten oddities and even some more ancient artifacts. Using 3D print materials based on clay or ceramic powder, it is possible replicate very old pottery. This will eventually make it less expensive for museums to exhibit a wider variety of history.
Here at AP Extrusion, many of us share an interest in recreating old automobiles, especially the muscle cars of the 1960s. 3D printing makes it possible to replicate the plastic components that have long since passed out of market. This enables us to restore a complete vehicle without spending years hunting down parts. We are always interesting in talking to anyone who shares our passion and in many cases, we may be able to help with your custom restoration efforts. Consider 3D printing as an alternative to any custom molding project and you will likely find the time and cost are greatly reduced.
Plastic’s Place in the Biosphere
March 16th, 2010Since it first came into wide-scale industrial use in the mid 1930s, polyethylene has been chosen as the preferred material for many applications. Most of these applications came about because polyethylene is low-cost, heat resistant, acid resistant, insulant and slow to biodegrade in nature. Among these properties, the last has proven to be more of a double-edged sword as each year we continue to produce 80 metric tons and the environment breaks down far less. Recent progress on biodegradable polyethylene has presented a partial solution, but many of the most common applications simply weren’t intended to rot under natural conditions. Most forms of tubing and cables only function effectively so long as they remain completely intact. The same can be said for most plastic car parts, electronic casings, food and drug containers, and many others.
Until recently, recycling remained our first and only effective strategy for sustainable use of “non-biodegradables”, but in 2008 it was discovered that a variety of bacteria called Sphingomonas can degrade polyethylene molecules. Since polyethylene does biodegrade very slowly in nature, a Canadian science fair student named Daniel Burd was able to isolate and eventually concentrate the specific microorganism(Sphingomonas) responsible for the breakdown. Though the right concentration does not exist in nature, high volume Sphingomonas can break down plastic in a few months instead of the 1000 years it takes now. It should also be noted that this organism is unaltered at present, though many companies are now proficient at bioengineering bacteria for specific purposes. In the future it may be possible to breed varieties of Sphingomonas that are even more effective at breaking down polyethylene and other types of plastic.
The Future of 3D Printing
March 16th, 2010Since the early days of science fiction, people have known that eventually our path of technological evolution would lead us toward machines that could create any physical object based on specified parameters. The birth of 3D printing in 1986 was our first real step toward achieving this vision and as companies realized the tremendous savings when compared to traditional prototyping techniques, many new branches of research quickly opened up. Though the first 3D printers could only use one particular type of plastic, the demand for other materials led to techniques for rapid prototyping with metal, glass, and clay, as well as other types of plastic and hardened resin.
The first commercially available 3D bio-printer was recently announced by a company called Invetech as being capable of printing tissue and organs at the cellular level. One of the most exciting spin-offs of 3D printing is a project called RepRap, which is open-source, meaning that all its blueprints and results are publicized and can be used by anyone freely. RepRap is the first known attempt at building a self-replicating machine, the ultimate goal being to have RepRap print more RepRaps. Having undergone several revisions already, RepRap can now print all of its own plastic components and the research is currently being targetted at the printing of whole circuit boards.
Part of the project’s stated goal is to “enable the individual to manufacture many of the artifacts used in everyday life” for “a minimal outlay of capital”, so it’s not that difficult to see where a few more decades of research could lead. With the right supply of power cells and raw materials, a single RepRap could concievably be given the blueprint for an entire building and then print up as many copies of itself as were needed to construct the building blocks and put them in place. Some have even speculated that advanced versions of RepRap will eventually be able to improve their own design, essentially beginning a path of AI evolution.
The Most Widely Used Plastic in the World
March 16th, 2010With so many varieties of plastic tubing to choose from, a design engineer has many difficult choices to make when prototyping a new medical device. Of all the materials used for such applications, polyethylene most often leads the way.
Introduced to the world of manufacturing at the time of FDR, polyethylene has since made many applications easier to manage, safer for consumers(compared to earlier metal counterparts), and cost-effective enough to mass-produce.
When choosing a type of polyethylene, mechanical factors always come first, because they are the basic requirements needed for a design to function. Fortunately, polyethylene is extremely versatile and most mechanical requirements can be met with many possible formulas. Cost must also factor into the decision, as all consumer products have a price point which limits their allowable manufacturing cost. Understanding the properties of the different grades can assist a design engineer in the selection of thermoplastic materials for products that use custom plastic tubing.
LDPE(Low Density Polyethylene) – The first invented grade of polyethylene, LDPE remains the most commonly used density. In addition to being useful for plastic tubing, LDPE is also used for plastic bags, food storage, computer/car components, general purpose containers, and many other things. While it has a lower tensile strength than the higher density grades, it has a higher resilience(maximum energy per unit volume that can be elastically stored) which makes it very flexible.
HDPE(High Density Polyethylene) – While it has many of the same applications as LDPE, it is harder, more opaque, and somewhat more resistant to heat and chemicals. It is often used for outdoor scenarios where there is a large temperature range as well as containment scenarios where chemicals need to be isolated from the environment over a wide area.
LLDPE(Linear Low Density Polyethylene) – Slightly harder to process than normal LDPE, LLDPE has higher tensile strength, impact resistance and puncture resistance. Basically this means that a thinner layer of plastic can remain intact under flexibility testing. Its primary use is in flexible tubing, but it is also used for plastic wrap, toys, lids, cable coverings and more.
UHMWPE(Ultra High Molecular Weight Polyethylene) – More expensive than most other grades of polyethylene, UHMWPE has the highest impact strength of any thermoplastic presently made. It is often referred to as high performance polyethylene and is typically reserved for “unbreakable” scenarios like artificial bone replacements, bulletproof vests, etc.
VLDPE(Very Low Density Polyethylene) – Because VLDPE is characterized by even lower heat resistance than LDPE, it is often used in packaging for frozen food and ice. Some tubing and stretch wrap is also made from VLDPE and it is commonly blended with other polymers as an impact modifier.
PEX(Cross-linked High Density Polyethylene) – PEX is almost exclusively used for long-term tubing scenarios. Many thermal properties of the plastic are improved by the cross-linking process. It maintains strength at a higher temperature and reduces flow. Under low temperatures, impact resistance, tensile strength and scratch resistance are improved. Cross-linking also improves the chemical resistance.
Eliminate guesswork in your next design project with Rapid Prototyping
March 16th, 2010If you’re a design engineer the last concern you want to have when your product is going into production is, “Will it work they way in which it was intended?” While oversights in design can be rectified post-production, it’s costly and timely – not to mention a lost opportunity for your company.
No company wants to lose market share due to a delayed product release, which could have been avoid had they chosen to elect rapid prototyping services to improve the design process.
The benefits of rapid prototyping services is quite simple: Design engineers can improve the accuracy of their products’ design by creating a 3D prototype model that will allow the various concepts to be tested before it’s manufactured and introduced to the marketplace.
But despite its growing popularity Rapid Prototyping technologies is underutilized by many industries that could otherwise benefit from its use. The biggest benefit of creating rapid prototype models is that it can produce a prototype model quickly, and at a low cost.
Wonder how quick the turn-around actually is for creating a rapid prototype?
More often times than not, manufacturers who offer rapid prototyping services can produce a model in hours, where it use to take days or weeks. Because of the expediency and efficiency of this service, it can decrease the typical time it takes to get a product to the marketplace up to 80%.
When you’re ready to minimize the risk and time delays in your next product design, consider contracting a rapid prototyping manufacturer—they are quickly becoming a valuable resource that design engineers can’t live without.
Nylon Tubing—the other tubing material choice
March 16th, 2010It’s not only plastic that leads the way in custom manufacturing tubing—nylon is just as useful and resilient.
Recognized for its tensile strength, and selected for its stability, nylon tubing has maneuvered its way into applications ranging from uses to transport vapor or liquid, for air and brake lines, or any other situation that requires flexibility and the ability to withstand repeated stresses over a long duration without negative effects.
Phew! That’s a lot to ask from nylon tubes. But regardless, the fact remains that utilizing nylon tubes in situations that will put increasing amounts of abrasion and friction on it is critical to ensure it meets the requirements of the task.
For instance, ideal for use on cooling systems, pneumatic controls, hydraulic lines and grease lines—nylon tubes-12 is less expensive to manufacture than nylon tube-11and is perfectly suited for these numerous industrial applications.
Customers who need Nylon tube-12 specify its use when they need to prevent vapor permeation, whether the nylon tubing is delivering fuel, or any other chemical liquid. This ensures that the equipment on which it is being utilized doesn’t experience failure or compromise safety.
But customers also have the option of manufacturing nylon tube-11 which is better suited for use in the food industry as it is made from materials that comply with FDA regulations.
Although this type of nylon tube is suited for other industries, such as for chemical companies, making the choice to use nylon tube-11 in use with transferring fluids whether alimentary liquids such as milk, beer or biological such as serum or blood—nylon tubes are a prime alternative to plastic.
The Places You’ll Go With Flexible Plastic Tubing
March 16th, 2010What is it about flexible plastic tubing exactly that makes it such a sought after tubing product?
Actually, the answer is rather simple as to why companies from automotive to medical or even home hobbyists for that matter, select flexible plastic tubing—it’s due to its availability in a wide range of sizes, shapes, and thermoplastics that provide for such diverse uses of flexible tubing.
Not only do these qualities make flexible plastic tubing an attractive choice, but also because flexible plastic tube is easily accessible to the marketplace that makes it a primary choice, particularly in a pinch. And it’s easy to install.
However, one is not only left to the stock availability of flexible plastic tubing at Home Depot or Lowe’s.
For industries requiring very specific design features of flexible plastic tubing for their equipment, they have access to custom plastic manufacturers who can readily assist them with their small diameter flexible plastic tubing needs. Now while the need could be as simple as installing a small diameter flexible plastic tube to finish off a connection in an airline; to those who require a more sophisticated flexible tubing solution such as that which may be replaced in a medical device used in the critical care of a patient during dialysis—the design of a small diameter flexible tubing requires a systematic approach in both design and manufacturing.
It should be reassuring for customers to know that flexible plastic tubing offers as much in terms of reliable performance for a water injection system as it does for a multi-fiber optical cable. But whatever the application, companies should consult with a custom plastic manufacturing company to have the added assurance that are using a highly quality flexible plastic tubing product.
The Trends in Medical Extrusion Tubing Keep Growing
March 16th, 2010Despite the economy, and the recent surge of job layoffs, there is one fact that remains—people still need quality medical care, and as such there continues to be a growing demand for high-quality medical extrusion tubing amongst those in the medical profession.
As a matter of fact, the average annual growth rate of extrusion tubing worldwide is calculated at 8%, and this is for good cause.
First, rapid advancements in medical device technology necessitate that custom medical extrusion tubing be an essential component for use in both invasive surgical procedures and after-care treatment. The small diameter extruded medical tubes are used in applications from transferring fluids to a patient during a transfusion or intravenous, or the medical extrusion tubing is used for an intubation or during anesthesia, to name a few.
Second, because small diameter extruded medical tubes are manufactured following industry regulations, customers are provided with a pre-sterilized, disposable, medical extrusion tubing product; giving the added assurance that the medical extrusion tube will assist in minimizing the spread of infectious disease during surgery or any other application.
While the reasons for using medical extrusion tubing are vast, there is one driving factor that has affected growth. It’s due to the competency of custom tubing manufacturing companies to meet the demands of the medical industry to make improvements to the extruded medical tubes manufacturing process, such as tighter tolerances or co-extruded new thermoplastic combinations. Employing new precision manufacturing techniques ensures that the medical tubing products are designed and developed to meet the stringent demands of their customers. And due to the growth in demand of medical extrusion tubing, the incentive is built in to respond immediately.