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Joel Longstreth

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PPE Isolation Gowns and Coveralls Simplified

Posted by Joel Longstreth on Wed, May 13, 2020 @ 04:21 PM

In only a few weeks, PPE has become part of the common lexicon.  Isolation gowns are fortunately not as in high demand as projected just a few weeks ago.  Hospital supply chain managers are now thinking in terms of being prepared for summer and fall surges and stocking up for the next round.  The term isolation gown is used loosely but interpreted literally in healthcare.    

We do not manufacture gowns.  We make rollstock which is converted into gowns.  Watch this video for an example.

Here is a condensed guide to the variations within the isolation gown species.  This is limited to gowns for medical personnel only and does not include European EN 13795 classification for patient gowns some of which are considered medical devices.  The CDC's NPPTL / NIOSH bulletin, delves into great detail about design considerations mainly about the base material's resistance to fluids.   While there are four well defined levels, it's basically the degree to which the fabric or plastic film resists fluids. 


A term which has been around for eons - "strike through" is a prime consideration.  Strike-through describes migration of microbes through the fabric.  It is critical in the design of all surgical drapes.  In the olden days long before mayo stands the surgical instruments were placed on a woven fabric.  Little consideration was given to wicking through to a scalpel.   A bloody instrument placed on the fabric created a superhighway for pathogens.  Probably shortly after the invention of the Mayo stand the ubiquitous mayo stand cover was a natural progression.  Mayo stands and nurse's back table covers both have a layer of polyethylene film laminated to nonwoven to prevent migration. 

The crux of the issues are summarized in this passage from the NIOSH bulletin:

selecting the most appropriate protective clothing for healthcare workers based on the recommendations, practices, and regulations. This challenge is complex because there are several terms (e.g., fluid-resistant, fluid-proof, impermeable, and impervious) used in the industry to define barrier resistance properties of garments. The term “fluid-resistant” usually refers to fabrics that resist liquid penetration, but may allow penetration with pressure. According to Taber’s Cyclopedic Medical Dictionary, “impermeable” means not allowing passage, as of fluids; impenetrable [Thomas 1997]. Calling a fabric “impermeable” or “impervious” usually means that the fabric prevents liquids or microorganisms from penetrating. Impermeable could be in reference to water, to blood, to viruses, or to all. The terms “impervious” and “impermeable” are often used interchangeably. Unfortunately, there is no industry consensus for using these terms. Therefore, manufacturers usually provide fabric or garment specifications associated with the standard test methods or standard classifications. In addition, due to the misleading use of these terms, the FDA does not approve marketing surgical gowns or drapes with “impervious,” “impermeable,” “fluid repellant,” or “fluid-resistant” labeling claims.

Like the FTC who has to prioritize chasing down false claims, many distributors are playing fast and loose with terminology. 

It is interesting to note that many gowns are marketed using these terms.  Apparently it is legal if the gowns are used anywhere but the OR.  The danger of exposure to bloodborne pathogens due to hemmorhage is equal in either environment.  In desperation, some nurses did not check with NIOSH or ANSI when they made makeshift gowns.


The test methods for determining susceptibility to penetration are well defined.

Much attention is paid to resistance to pressure.  The chance of a pinhole developing is most likely due to continuous pressure from leaning or resting.  The test method is different than most used to assess the durability of polyethylene film.  They are made to determine how a film withstands a sudden impact. 

The resistance to fluids determines the " class " of gown

Table 3: ANSI/AAMI PB 70:12 classification of barrier performance of surgical gowns, other protective apparel, surgical drapes and drape accessories.

Table 3: ANSI/AAMI PB 70:12 classification of barrier performance of surgical gowns, other protective apparel, surgical drapes and drape accessories.
Level1 Test Liquid Challenge Result Expected Barrier Effectiveness
1 AATCC 42 Impact Penetration2 Water ≤ 4.5 g Minimal water resistance (some resistance to water spray)
2 AATCC 42 Impact Penetration Water ≤ 1.0 g Low water resistance (resistant to water spray and some resistance to water penetration under constant contact with increasing pressure)
AATCC 127 Hydrostatic Pressure3 Water ≥ 20 cm
3 AATCC 42 Impact Penetration Water ≤ 1.0 g Moderate water resistance (resistant to water spray and some resistance to water penetration under constant contact with increasing pressure)
AATCC 127 Hydrostatic Pressure Water ≥ 50 cm
4 ASTM F1670 Synthetic Blood Penetration Test (for surgical drapes) Surrogate Blood no penetration at 2 psi(13.8 kPa) Blood and viral penetration resistance (2 psi)
ASTM F1671 Viral Penetration Test (for surgical and isolation gowns) Bacteriophage
no penetration at 2 psi(13.8 kPa)

Nonwoven is the classic material of choice.   It is of course, very porous at best and does not provide a water barrier if it is not "poly coated ".  Poly coated means poolypropylene nonwoven which has been extrusion coated with polyethylene for water barrier. 

Where we fit in: we make the rollstock which becomes truly impervious isolation gowns made from polyethylene film made by the blown film process.  It is by definition water proof and stronger than extrusion coated because it is oriented in two directions. 

In my opinion, a nonwoven gown falls short of being even a security blanket, especially with a big open area in the back. 

In the short term, it's the wild west for opportunists who are getting daylight robbery prices while it lasts. Parse the claims and definitions.  Caveat emptor. 


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Topics: isolation gown, impermeable isolation gown


Posted by Joel Longstreth on Fri, May 01, 2020 @ 06:13 PM

Verbal shorthand when thrown around casually can lead to misunderstandings especially to an industry insider who takes these terms literally. 

Herewith is a short explanation of some common acronyms for plastic films in plain English starting with the basic chemical building block.  


The only thing common to all three is ethylene, C2H4 or " C2" for short in the petrochemical realm.  This building block is a monomer.  String them together with variations on a theme and you got the polymer ( poly vs. mono )
polyethylene. PE, PEVA and metallocene PE are all polyethylene .  

Poly Vinyl Choride or PVC for short is ethylene conjoined with chloride to make Vinyl Chloride monomer H2C=CHCl.  String together a bunch of these and you got POLY vinyl chloride loosely referred to as vinyl. 

Tangram Technology Ltd. - Polymer Pinking

image credit Tangram Technology UK

This is where the similarities end.  The differences in these two largest volume thermoplastics are stark.  
To achieve difference in softness or stiffness, PVC needs to have what are called plasticizers added.  Because of the chlorine, PVC is naturally self-extinguishing.  Polyethylene PE is just compressed natural gas so it is very flammable.  PVC is about 35% more dense than even the highest density of polyethylene, or HDPE #2.   PVC is a "polar" molecule which makes it a natural for RF sealing.  PE is inert and must be heat sealed.

Metallocene PE ( mPE ) is polyethylene made with a metallocene catalyst.  It is imperative to remember metallocene is a catalyst, not a comonomer.  There is a wide variation in the species.  Metallocene really is the Holy grail because it allows precise molecular weight distribution.  Think molecules made by cookie cutter. 

We have written exensively about PEVA.  This link takes you to three blog posts which explain the differences in more depth.   PEVA has caught on because it is slightly polar and can be RF welded with a minimum of modification to heirloom RF welding apparatus.  We can mimic the properties of PEVA with a blend of metallocenes.

If you still have questions, please contact me 513 238 8552

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Topics: PEVA

Plastic - a Weapon vs. Coronavirus

Posted by Joel Longstreth on Fri, Mar 20, 2020 @ 06:34 PM

Scroll down for update

In a crisis, political correctness and platitudes get relegated to abeyance. Only weeks ago the bane of our existence was plastics.   Bashing plastic straw men reached a tipping point in 2019.

coronavirusdatingsmothered in Purellmountsinaigowns


 The Fauci " curve " would be an outbreak spike without plastics.

Here we go again.  In the aftermath of hurricane Harvey, plastics came to the rescue.

In the midst of the coronavirus crisis, plastic is once again the unsung hero.  You don't see articles
about plastic breaking the transmission chain.  The mention is mostly passing, usually about how long the virus can stay alive on specific surfaces.  Update May 22, 2020 The CDC says COVID 19 does not live long on surfaces.  Sanitizing is like sooooo March 2020 !

" These plastic bubble helmets are connected to ventilators to help patients breathe."
ABC chief foreign correspondent Maggie Rulli on assignment in Italy March 20,2020

Plastics plays a key role in both mitigation and cure.  If we are indeed on a war footing, plastics is a weapon against the coronavirus.  hazmatdocBPI Essential Products

Take a look at these images.  The common thread - plastic is a barrier between the virus and humans.
It's basic fundamental HACCP 101.   

Did you know ?  Even the nonwoven gowns and N 95 respirators are made from fossil fuel plastic, not organic hemp. 




If the plasma therapy turns out to be viable, would single-use plastic or glass bottles be the preferred choice ?
Israel just flew in 10,000 hydroxychloroquine kits.  Were they packaged in woven burlap or plastic ?

The reason post-op infection rates are low is simple.  The sterile plastic devices are used once and disposed as biohazard in single use plastic bags.  The argument for the short service life of disposables is no longer.  There is zero chance for seed populations to infect another patient.  If this mode was not effective, we would still be washing and recycling drapes.  New York Presbyterian has a shortage of masks because they are not taking any chances.  They are going through 40,000 to 70,000 daily compared to their normal usage of about 4,000.  Source: Craig Smith, Chair Department of Surgery / Surgeon in Chief  NYP CUIMC.

(  Let's remember basic econ here - a shortage is defined as an insufficient quantity of a commodity at the prices the market wants to pay.  When demand spikes due to an acute change in consumer behavior, voila !  You got a shortage.  We are seeing firsthand the invisible hand stepping up. )

We make film destined for opthalmic drapes, ostomy bags, under patient capillary blankets and other dermal contact medical devices.  Would you really want to be the patient who gets a hand-me down device ?  There are no poll numbers, but I suspect most of the greens would save themselves, not the planet given a choice.  If the government declares plastics a non-essential industry, recycled devices and bandages will become SOP (standard operating procedure ).

" Doctors are putting masks in ziplock bags so they can be reused for up to a week."
ABC anchor David Muir March 20, 2020.


Governor Mike DeWine of Ohio is pressuring the FDA to fast track approval of mask sterilization. 

It's ironic that this is happening just as we are about to launch version 4.0 of a reusable bag.  Suddenly, the data about microbes travelling on reusable bags has become relevant.   A major defense of single use bags has been their cleanliness vis-a-vis reusable bags.  The data on microloads has been out there for years.  This has led to re-thinking bag bans.


The virtue signallers have a dilemma.  If they show they care more than everyone else by using single-use plastic bags, they will tacitly endorse the plastic-industrial complex.   Who knew there would be comedy gold in this tragedy ?  Us humans are the root of all problems, so why keep more of them alive ?

Once again expediency and survival trumps political correctness. 


At this writing, resin producers claim there is still substantial demand.  In my own direct experience, I have not seen nor heard of eco warriors refusing to buy toilet paper packaged in plastic.  MDPE for soft goods overwrap will be strong in the short term. 

The world will be different in the aftermath of the current unpleasantness.  Time will tell if plastic reverts to goat or remains a hero. 

Update May 14, 2020
To the chagrin of plastic haters, single use plastic is only going to increase dramatically.  Open kiosks are out, prepackaged is in.   We will be greeted at events with kits consisting of a mask and spray. 



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Topics: plastics recycling,, extended producer responsibility, plastics toxic, eco friendly plastic,, virtue signalling, plastic bag bans, coronavirus spread

Plastic Films Substitution

Posted by Joel Longstreth on Fri, Oct 04, 2019 @ 06:13 PM

Everybody wants replacements for politically incorrect plastic films to be exactly like the original.  No property trade-offs.  No exaggeration. 


Would these same people expect the same results from direct substitution of stevia, xylitol or saccharin ?

There are many drivers.  Back in the 1990's when PVC started to fall out of favor, we got calls for PVC replacement.   The major complaint about our metallocene which mimicked the "hand" of vinyl was that it did not seal in the heirloom RF sealers.  The expectation was that a non-polar molecule would behave just like a polar molecule.  Reluctantly, new sealing techniques were developed as a work around. 


Skip ahead to this past summer.  We got literally dozens of calls for our equivalent to PVC cling wrap for packaging corn because WalMart does not want PVC in their stores.  Even if they found a polyethylene that was clear enough and ran in the usual machine, the shelf life would not be the same due to difference in permeability. 


PEVA ( polyethylene with ethylene vinyl acetate ) has emerged as the film of choice for shower curtains because it is not PVC and is sealable by RF with minor modifications.  

We wasted a lot of resources developing a substitute for PVC in commercial wallcoverings.  The greenbuild culture despises PVC but they are stuck with it.  Only PVC passes E 84 because it is naturally self-extinguishing.

The interest in percieved sustainable films has hit a tipping point as products are being designed for more of a "circular" than "linear" economy.   Designers are finding there are many frustrating hurdles to overcome.



Just when you think you've seen it all department - today somebody inquired about a substitute for a coextrusion of LDPE / Nylon / LDPE.  They wanted a certifiably compostable film just as tough as the coex structure with the sealability to nonwoven.  At first I thought it was a prank.

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Topics: PVC free plastic, PVC free, PEVA film, PEVA, Non - PVC, PVC substitute, sustainable packaging,, green plastic

PE Film Lead Time Factors

Posted by Joel Longstreth on Wed, Apr 24, 2019 @ 06:05 PM

The ship date for custom PE film involves much more than a first-come-first-serve queue.  An extruder who runs their backlog in this fashion or has a salesman running the backlog is not long for this world.  

ancient pyramid art

This is nothing new.  Egyptologists have determined that customers and suppliers have been at loggerheads for thousands of years. 

The primary consideration in setting up a backlog is minimizing scrap.  The scheduler's agenda is to consolidate a sequence of films made out of the same PE resin as long as possible to avoid transition scrap.  With resin cost at about 75 cents per pound, every pound of scrap is really about $ 1.00 lost factoring in labor, electricity and overhead. 

This is crucial to survival in coextrusion.  Complex 7 and 9 layer films can literally take all day to set up. 

A medium scale extrusion line puts out about 500 pounds an hour.  What would you do ?

It's best practices to have some leeway in ship dates.  We promise our orders for "week of _____ ".  A smart play is to promise a Thursday ship date.  4 out of 5 chance it will ship early or on the date.  1 in 5 chance it will be a day late and so what ?  only a day late. 

It's also best practices to have a few dummy orders in the backlog to both act as a cushion for breakdowns and allow for opportunities.  If an order comes in with a ship date 3 to 4 weeks out for a resin running today, it makes common sense to move it up in the queue to avoid setup scrap instead of running it as a stand-alone 3 weeks later.

Distant secondary considerations are width and thickness changes ( there's the central theme of avoiding scrap again ) followed by pigmentation.  Cleaning out after colors is time consuming and messy.  The line must be shut down, purged, what is called the screen pack / breaker plate must be changed.  The ordeal is followed by an expensive, frustrating waiting game while the remnants of the color clear out.  

Back in the day, we had a shrewd customer who went out of his way to pay his bills every Saturday.  A check for all invoices in the week would show up like clockwork on Monday morning.  Why ?  To tempt the film extruder to deviate from fundamental priorities.

Of course, there are a few justifiable exceptions.  Re-work of returned or defective product or doing an occasional favor for a good customer who is out of film and shut down.  

So now you know why:

Coextruded films have such extended lead times

shrink films have such a wide variation in MD / TD shrink ratios
( the order goes on the machine that needs work )

pigmented films have longer lead times

Are you wondering where is our proof that first-in-first-out doesn't work ?  That's easy.  The outfit we sold out to in 1984 ran orders in the sequence received.  It took them 3 years to declare bankruptcy.


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Topics: LDPE film, poly film, polyethylene film

Post Consumer Recycled Content " Gen 3 " Solution ?

Posted by Joel Longstreth on Mon, Apr 30, 2018 @ 12:58 PM

Giant retailers and consumer product companies are frantic to be perceived as green and sustainable.  Meantime, the major plastic resin producers are doubling down on conventional fossil-fuel based resins.  Sounds like a script straight out of  The Innovator's Dilemma.




" Gen 1 " is defined as plastics derived from fossil fuels.  

"Gen 2" is plastic derived from agricultural sources or "biopolymers " the option of choice for hard liner zealot greenies.  While a truly compostable plastic must be made from ag sources, plastic derived from plants are not by definition biodegradable.

The decision is complex

If plastic packaging made from agricultural sources crowds out arable land, food costs will skyrocket.  The major food processors have seen what happened with ethanol.  

It's all about perception.  Anything derived from fossil fuels is perceived as inherently evil and made from a source which is not sustainable.  Braskem has done a fabulous job marketing their "green" polyethylene and polypropylene made from sugar cane.  They get a premium and won't talk to you unless your volume is 1,000 metric tonnes annual - take or pay.  These resins do not biodegrade any faster than petroleum-based plastic.  Braskem is putting on a billion pounds annual capacity in La Porte, TX.  The feedstock ?  Fossil fuel natural gas.  Their CEO went so far as to praise the U S ( fossil fuel ) feedstock situation. 

With painstakingly politically correct word choice, Lego announced their selection of " green " plastic.  

There are two approaches to a quick fix.  Either "greenwash" ( defined as no change, spin only ) or make hasty changes out of fear of social media.  Notice how much emphasis is put on what a product does not contain these days ?

Bisphenol A is an excellent case study.  " BPA free" is an insult.  Only polycarbonate and PVC use it as a catalyst.  There are trace amounts in the final product.    If your product is made with any other resin, just say        " BPA free" and voila !   You take advantage of the consumer's fear and lack of understanding.which may be just enough to stimulate an impulse purchase.

Sometimes the alternative to the vilified material is worse.  Those who reacted to NGO's clamor for a BPA ban by substituting BPS and other materials were the biggest losers.  In retrospect they look impetuous.  The quiet epilogue: BPA's recent clean bill of health despite being put on California's prop 65 list and the EU's possible ban.  Did the NGO's give a public apology ?   A "never mind" a la Emily Latilla ?

Of course not.  The disingenuous virtue signaling malcontents just move on to another faux outrage cause.

The latest angle is apparently a hybrid of fossil fuels and potato starch from a company called Biologiq.  They offer both compostable biopolymers and combo fossil fuel resin / biopolymers.  They claim their resin initiates a reaction which renders the conventional resin truly biodedgradable.  I have not seen convincing supporting science.  Just the same, the CEO of Walmart is pushing hard to get whole produce packaging transitioned immediately. 


What is quietly catching on is post-consumer recycled content.   While this approach does not appease the greens for whom fossil fuels is anathema, it is a compromise. 

Consumers feel good about recycled content for whatever reason.


The major resin producers are not working on it.  They have their hands full with virgin resin.  Resin distributors are partnering with outfits who reclaim and repelletize plastic scrap.   Feedstocks are either the bags returned at the supermarket or the shrink wrap and stretch wrap from the back of the store.  The consistency of the initial product offerings is impressive given the variation in feedstock. 

There are limitations on the amount of post consumer content (  Burying floorsweep in the core layer of coextruded has been around for a long time; overnight shipping envelopes is a ubiquitous example. ) - mainly consistency and FDA approval.  Reclaimed from whatever source is by definition so we will be resigned to adding some virgin resin.   While some extruders are making claims about having " FDA non-objection " letters for prolonged and direct food contact, we have not seen one.  If we use post-consumer resin for food packaging, we would lose our Kosher approval. 

2020-2021 Brentwood Plastics Kosher Certificate small

Click on the image to enlarge.


The prime resin distributors are telling us post consumer resin will be a standard offering by the end of the year.  
We are developing select non-food applications such as trade show bags, reusable bags and barrier tape.

Over 100 years ago, H L Mencken said " For every complex problem, there is an answer that is clear, simple and wrong. "



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Topics: eco friendly plastic,, sustainable packaging,

Plastic Shortages

Posted by Joel Longstreth on Wed, Sep 06, 2017 @ 03:44 PM

Part of Harvey's aftermath will be a shortage of plastics.  The general public cannot see it yet.  Many plastic processors and especially their customers are in denial.  Many large processors have shut down and sent their employees home.  For us old timers, recent events conjure up shortages of 1973 - 1974, 1998 and 2005.




The irony is that black plastic trash bags are badly needed in Houston now.  

The following is a recap of causes and outcomes of the previous shortages.

First, let's review the definition of a shortage.  A shortage is simply not enough of a commodity available at the price the market wants to pay.  Simultaneous to the oil embargo, there was a shortage of beef.  Vegetarians were not particularly concerned.




                                                  1973 - 1974

The plastic industry was a teenager. 6 years earlier, Dustin Hoffman's character Benjamin Braddock got the famous career advice -  plastics !   Resin was made either by chemical companies who were not basic in feedstocks or by a few petrochemical companies.  The chemical companies bought ethylene and propylene on the "spot" market.  When the oil embargo hit and monomers were in short supply, guess who got first option on ethylene and propylene monomer?

Plastic processors went on allocation based on historical purchases.  List price for polyethylene was in the 15 cent per pound range.  When Nixon instituted wage and price controls, people got creative.  Suddenly there was a plethora of material available in the 50 to 60 cent range.  It was labelled "off-spec".  One legacy of the big one:  no more "list" prices for resin.  There was resin, but not much for 15 cents a pound.  

During the roughly 16 months of the shortage, pricing was hour by hour.  The phrase "prevailing price at time of shipment" was added to the terms and conditions of sale.  Look closely in the fine print of an old plastic processor 's terms and conditions and you will probably see it.  

The shortage pricing collapsed in a matter of days.  Many plastic manufacturers reinvested their windfall profits in more capital equipment thinking the party would go on.  Instead, it lead to a glut of overcapacity.


was short lived.   Processors on allocation quietly exported their excess resin to maintain their allocation. The resin companies figured out they were better off dividing the fishes and loaves among their smaller customers for higher margin than unloading in bulk to large customers at rock bottom prices.  Ever since, credit managers have had more sway.


was the aftermath of Katrina and Rita, often referred to as "Katrita".  Natural gas spiked to an all-time high of $ 15.  Search volume for "price of plastic" also spiked.  Buyers who were not around for 1973 / 74 simply could not believe the price for a cheap commodity could go up that fast.  The lasting effect of Katrita was agreement upon the CDI as a basis for price adjustment.  The other lasting effect has been discipline.  There was major bloodletting at the resin companies in 2006.  Ever since, the resin producers have shown remarkable discipline. Now it's no forecast, no resin.  They no longer just make resin for it's own sake. 


Skip ahead to present day.  The initial shock of Harvey has worn off.  Now customers want to know when they will get resin and when.  What is reminiscent about 1988 is smaller processors are getting better access to resin than large volume processors.  Smaller processors defined as less than roughly 25,000,000 pound per year usage have been relegated to buying through prime distributors.  The large volume users are calling distributors with orders for multiple railcars.  They are perplexed when their orders are respectfully declined due to overriding concerns about keeping long-term smaller customers stocked with material.  Several large plants have simply sent their people home.

There are three components to producing resin - monomer, polymerization and transport.  The monomer and polymerization bits are coming back quickly.  The transport part is the crux of the equation.  There is an embargo on rail traffic to most of Houston.  Anyone who has dealt with railroads knows they are not going to put equipment on tracks until there is at least 105% certainty that the tracks are intact. 

Plastic processors simply do not know if they will get resin, when, how much or what the replacement cost will be.
Many are reluctant to snap up resin because they are either in denial or they still remember getting burned back in October of 2008 when resin prices cratered 30% in a few days.  
The "prevailing price" lingo won't fly today.  The good news is there is plenty of capacity ready to fill the void.  If past is prologue, the Harvey shortage will end with a whimper.

Harvey's aftermath is a slow-motion catastrophe.  Volume buyers of finished product are in denial.  Behind the scenes, volume processors have resigned themselves to being out of some grades and shut down by November. The conversations between WalMart buyers and their suppliers are going to be interesting.  

Processors and their customers who eagerly anticipate running reverse auctions when 18 billion pounds of capacity comes on stream are going to be disappointed.  Their is plenty of worldwide demand to take up the slack and resin companies are disciplined about forecasting and scheduling.

Question: If polyethylene needs to be rationed, what items should be priority?

Who should decide?


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Topics: harvey plastic, plastic shortage, price for plastic

PE Resin in the Age of Madmen

Posted by Joel Longstreth on Tue, Jan 17, 2017 @ 06:10 PM

While spring cleaning, we found a cache of 1960's era letters from Union Carbide.  





The letters were from big shot execs in the mid-town Manhattan offices.  All were perfectly individually typed with no errors ( whiteout probably did not yet exist ).   While Don Draper was working on ads for mass marketing, the senior execs were incredibly creative by tying in first day of issue stamps to their new resins for the narrow nascent blown film industry.

Of course there were many things nostalgic and laughable - six cent stamps, new applications such as shrink film, juice packaging, frozen food packaging.  Recycling ?  Re-what ?  Linear Low Density was over a decade in the future.  In the First Man on the Moon issue, they bragged about their two billion pounds of capacity.  They went to great lengths to show literally how far their resin would stretch - to the moon and back many times. There is at least 35 billion pounds of PE capacity coming on stream in the US in the next few years.    

In the late 50's the commercial feasibility of blown film was uncertain.  Today there are over 27,000 known blown film shops.

Reminds me of when our founder used to line up his three martini lunches on successive days when he worked for USI Chemicals.


How times have changed.  

Enjoy the gallery.  ( Click the enlarge.jpg below the slide show for full screen )  Who knows ?  Maybe the collection will appraise at $ 5 at the Antiques Road Show in the year 2100.


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Topics: LDPE resins

Designing for Recycling and Sustainability

Posted by Joel Longstreth on Thu, Jan 05, 2017 @ 06:07 PM

Cradle-to-Cradle, Recyclability, Sustainability and reclamation have historically been low priorities in design considerations.  The biggest obstacle to these goals is dissimilar materials in the same product.  Just as form follows function, selection of raw materials teamed up to do a job is determined by the properties raw materials can deliver.


Recycle Across America correctly attributes the recycling collapse and crisis to contamination.  

"... the collapse of recycling is primarily due to high contamination levels in the recycling stream.  Contamination cripples the economics of recycling.  The process to remove contamination reduces profitability, driving up the cost of recyclables, thereby preventing many manufacturers from reusing recycled materials. As a result, they continue to deplete finite resources at alarming levels." 

Note how economic sustainability dovetails with environmental sustainability.  The recycling business is tough at best because prices drop when there are more recycled materials are on the market.  There is not enough margin to absorb the additional cost of sorting.

It's not complicated.  The more dissimilar materials are contained in a product, the more difficult it is to
recycle for practical purposes.  If a product contains more than one polymer, it should be labeled a resin identification code ( or RIC for short ) symbol 7.  7 is the least recyclable.  It is the recycling stream China refused to take anymore which can be traced directly to the documentary " Plastic China."


Sweden has it down to a fine art.  They claim only 4% of their discards end up in the landfill.  There are two reasons:
1.  they have over 14 recycling bins for purity

2.  Germany is responsibly burning trash to generate power.  The program is so successful they are scrounging from other European countries.

So just make the product out of the same resin.  Simple solution, right ?
Problem: one resin can't deliver all the attributes needed. 

For years, coextruded multiple layer films was very cool.  Us monolayer folk were considered simpletons.  The dissimilar resins incorporated into a multilayer structure are by definition #7's.

At this juncture there is the what sociologists call " cultural lag " to deal with.  We just got an inquiry from a major pet food manufacturer looking for a recyclable structure.   They are using a classic legacy polyester laminated to polyethylene with a trap print.  They want the exact same thing only recyclable.  They were deaf to our recommendation that a lamination of the right polyethylene in both layers would be plenty strong and recyclable # 4 with only a small trade off of gloss.  They said this would not be an option because they were sure the consumer prefers the high gloss.  The marketing geniuses know which customers prefer gloass and which prefer matte finish for which specific products.  Impressive. 

Often the resolution to a problem is meeting halfway.  This mailing envelope solves the debate over paper or plastic.  Instead of an all polyethylene #4 recyclable envelope, it is made from both polyethylene bubble pack and kraft paper.  


Proponents of plastic often ask why cut down a new tree when you can use an old dinosaur ?  The rejoinder is usually "you're still usin' fossil fuels, man".  This brilliant example of an unrecyclable #7 satisfies all demographics.  Proof that it satisfies the demands of the consumer for green products is it's ubiquitous presence in UPS stores.  

A cotidien example of several resins in one product is a soft drink cup with a straw and lid.  It has three different polymers with three different job descriptions:  The stiff and pliable straw is polypropylene, the rigid lid is polystyrene and the paper is coated with low density polyethylene.  One resin is not versatile enough to do all three jobs.

At Sustpack2016, the common threads of marathon presentations by large companies were source reduction and landfill reduction.  They have all made great initial strides mainly through reduction of corrugated packaging. Just my opinion - it will be more difficult to maintain the same rate of progress after another few years.  Corrugated recycles allright.  It also cuts down trees and uses oodles of fossil fuels.  Chemical runoff is minimal compared to decades ago.  

Consumers feel best about recycled content to assuage their irrational conditioned consumer guilt.  Using less, or source reduction, is the most incontrovertible way to go green.  But that's too abstract.  Post consumer recycled looks like it's going to be the next big thing. 

It's an issue for not just the flexible packaging industry.  The green building culture is scrutinizing materials with emphasis on cradle-to-cradle. There are several recent success stories such as the Long Center for performing arts in Austin, TX.


This is not new.  Humans have been recycling construction materials for millenia with an efficiency motive. Construction waste is one of the major contributors to landfill, but that's another conversation.  Here is a great infographic about recycling across the globe and in recent U S history:

Like everybody, the meeting and convention industry is under pressure to show they are going green.  

Recently, it has become common practice to place a recycling dumpster next to the dumpster for non-recyclables.  What the convention industry used to pitch is turning out to be a massive trove of raw materials.
Here's the bargain: the recycler gets the cast-offs for free.  His cost of goods is the cost of hauling and sorting.

A big problem for both conventions and builders alike is carpet.  Carpet can have several components which makes it hard to sort.  Despite this obstacle, carpet recycling is catching on.  Cleaning and re-shipping carpet is a major headache for convention contractors ( the people who put up the booths, signage and install the
carpet ).  For example - Freeman the industry leader, has at any given moment 300,000 square yards of carpet in a cook's pot being cleaned and recycled.  The trend is toward nonwoven single-use polypropylene #5 used one time and sent to the recycler.  There will be a tipping point if the price drops to where the cost is less than transport + cleaning + transport again. 

The bad news is that even if products could be made with only one resin, it would not be a solution.  The major obstacle to recycling is indifference from the general public.  Proof is the low recycling rate of water bottles.  They are made from polyethylene terephthalate ( PET ) #1.  PET is the only commodity resin FDA approved for 
food contact and medical after repolymerization.  The recycling rate has dropped to 30.1 %.  More than 1 in 3 water bottles are discarded despite the efforts from giants like Coca Cola to make recycling easy.

Could it possibly be that consumers just aren't that concerned about the environment and only pay lip service ? 

It's better virtue-signalling fun to blame and vilify evil corporations.

For more information on the 7 basic commodity resin identification codes, watch this short video.


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Topics: plastics recycling,, sustainability, resin identification codes, RIC

Multilayer Packaging Lexicon

Posted by Joel Longstreth on Mon, Dec 12, 2016 @ 04:43 PM

Humans like to communicate in acronyms, abbreviations and inside lingo.   After I set up an appointment for a medical test, I got a call back.  They said I didn't have an oth.  " What's an oth ?"  " An authorization, sir "   Brings to mind the scene in " The Heat"

The flexible packaging business is no exception.  The written descriptions of multilayer packaging structures can be confusing.  Here are some plain explanations of commonly encountered cryptic abbreviations followed by some examples:

/  designates a dividing line between two layers
adh.  short for "adhesive"
BOPP  biaxially oriented polypropylene
COPP  copolymer polypropylene
CPP  cast polypropylene
EAA  ethylene acrylic acid
EVA  or VA  ethylene vinyl acetate ( should specify % of VA copolymer )
EVOH  ethylene vinyl alcohol  natural habitat is in the core layer of coex for barrier
ga.   gauge  one mil = 100 " gauge"  manufacturers chisel thickness, so ".94 ga." is as close to 1 mil as you'll find for PET; 
       "48 ga." is popular in PP

foil   foil
HDPE  High Density Polyethylene
LDPE  Low Density Polyethylene ( most common sealant layer of a flexible lamination )
LLDPE  Linear Low Density Polyethylene
MDPE  Medium Density Polyethylene
METOPP  Metallized Oriented Polypropylene
METPET  Metallized Polyester
NYL    nylon
PA  nylon
PE  polyethylene
PET  polyester ( not to be confused with polyethylene terephthalate which has the same abbreviation )
PPFP  paper poly foil poly
poly  polyethylene
PP  polypropylene
prt   print
PVDC  polyvinylidene dichloride ( a/k/a Saran )
surlyn    Surlyn
tie    tie layer ( always found in coextrustions, never in laminations ).  necessary to deal with the difference in rheology ( viscosity ) of different layers.  
wht  white

Thus, a callout like this:

PE / adh. / METPET/ adh / CPP

would in English mean:  LDPE sealant layer ( the PE layer is always the sealant layer ) laminated to metallized polyester laminated to cast polypropylene.

When you encounter " LAM" in between slashes, it means same thing as adhesive.  short for "lamination "

There are a zillion possible combinations.  If you run into one you can't translate, call us.

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Topics: coextruded film, multilayer film, coextruded, coextruded plastic, laminated films

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