We blog only about timely and relevant topics.  The software does not allow rearranging posts, so they are chronological.  You can browse by topic or keywords by scrolling down on the right side.

Brentwood Plastics blog

Prime vs. Off Grade Plastic Resins

Posted by Joel Longstreth on Fri, Oct 16, 2015 @ 04:48 PM

Plastic resins are made by major petrochemical companies.  The choicest cuts are sold by their direct sales force or through their "prime" distributors.  So who sells the near miss or transitional resins which are not exactly ready for prime time ?

Starting with definitions is difficult because there are no written industry standard definitions of most terms pertaining to resins in this realm.  There is no controlling legal authority which oversees the distribution of off grade resins.  Caveat emptor.

A "major" is short for a major petrochemical company which manufactures plastic resin.  A "broker" is an entity which takes title to the resin which the major deems to be not "prime" resin which falls within the target criteria. The majors sell prime through their direct sales force and prime distributors.

A data sheet lists certain key properties which define the characteristics of a resin. The first - melt index or melt flow - describes viscosity.  This tells the processor the most about how the material will behave and how it will affect the outcome of the part or material.  There are other criteria but going into depth would be too far in the weeds. 

Each of these criteria has a target and acceptable range for what is considered to be "prime".  These are not rigid and fixed.  Rather, they are at the discretion of the product manager at the resin producer.  The parameters change depending on the available supply.  When resin is plentiful, the parameters tighten up.  When resin is "tight", they widen.  It's all a function of what the product managers believe they can get away with.

When a product manager gets a report of fresh lots, she decides which ones are prime and which are considered "off grade" or "near prime".  The prime material gets "certs" and is sold through their direct sales force.  What falls outside the parameters is called "off grade" or euphemistically "near prime", "pencil prime" or "excess prime".  Other lots are called "transitional" which means resin made transitioning from one grade to another. 

Off grade, or OG for short, is sold through "brokers ".  By selling to a third party, the origin is obfuscated. Brokers  are supposed to be discreet and sell off grade to customers who are not direct customers of the same majors and preferably into a different application than originally intended ( It gets interesting when brokered resin finds it's way to prime customers ).   A business model which relies on somebody's mistakes at first sounds like a scary business model.  When resin is "tight" or when the majors are trying to raise prices, the brokers don't have much to sell.  The truth is there will always be material available which is rejected by processors. ( We reject several railcars annually produced by ISO 9000 certified major resin companies.  )

The most ethical and truthful brokers graduate to become what is known as "prime" distributors.  They distribute prime to smaller processors not called on by the major's direct sales force.  

It's easy to spot a newbie resin buyer.  They are too smart by half.  They make the rookie mistake of shoving an invoice from a distributor in the face of the direct sales rep.  " I can buy the exact same thing from your off grade broker for 4 cents a pound less !! "  Maybe so for one car.  After that, their reputation precedes them and they get no more deals.  Experienced buyers know the importance of emptying / returning a car quickly so the direct sales rep does not see the car which came from his own plant. 

Fun fact: there are no prerequisites to becoming a resin broker.  

Many brokers misrepresent material while others are ethical and disclose fully the good, bad and ugly about specific lots.  Processors operating on razor thin margins are tempted to save money with resin that's "not exactly" and brokers are tempted to misrepresent to move their inventory. They hope the processor won't know the difference.  Problem: the processor lives with the material and does know when the raw material is not as advertised.  Here is an example: .  
The ramifications go beyond the relationship between the processor and the resin producer.  The finished properties of the plastic film or plastic part within a lot or lot-to-lot are affected with variability of raw material.  FDA approval is meaningless.  Just change a few words in a word document and the broker transforms off grade into FDA approved plastic resin.  It's legal and goes on every day.
So how can you use this information ?  When doing the due diligence on a supplier, ask them preferably in person if the resin they use is "prime".  Don't be shy.  Ask to see FDA letters and invoices ( for the resin they use to make your product along with "track and trace" records ) with the price of the resin blocked out. If the letterhead is not from a major or authorized prime distributor, it's circumspect.  There is an exception.  Some brokers distribute "generic prime" which has been tested and sometimes blended to fall within specific ranges.
Many large brokers have what they call " generic prime " which is analogous to private label brands.  This is usually fair quality and does suffice for utility applications.
Read More

Topics: plastic resins, LDPE resins, PE resin, PE, prime plastic resin

Polyethylene Resin Factors of Production

Posted by Joel Longstreth on Tue, Sep 20, 2011 @ 05:01 PM


The price for polyethylene depends mainly on the factors of feedstock, or monomer, pricing and exchange rate. 

Exchange rate has a direct bearing on domestic prices because it affects export resin sales.  If the dollar is weak, dollar denominated resin becomes more attractive for export sales.  US processors simply have to pay the same price as export.

Feedstocks for so called "petroleum plastic" or "petroleum based plastics" are either oil or natural gas.  In North America, we derive resin from natural gas with the exception of polypropylene ( PP ).  Polypropylene is a by-product of the refining process; approximately 80% of North American PP is derived from oil. In the middle east and other places, they make resin out of naptha - the creme de la creme of a barrel of oil.  Naptha cannot be refined into gasoline or motor oil.

The US becomes the really low cost producer when natural gas is low and barrel oil price is high.  This is referred to as "feedstock imbalance."

Ever since Rita and Katrina combined to push natural gas prices to $15 / MCF, resin producers, processors and their customers have struggled to find a mutually agreeable benchmarking index.  While CDI ( ) is referred to most often, CDI has been challenged by resin producers often.

Here are a few complicating factors:

Lead time  Commodity resin manufacturers do not carry much inventory.  To have resin in inventory, processors must forecast 6 months in advance plus allow 5 weeks in some cases for a car of resin due to the X factor of the railroads.  When customers hear the price of resin has dropped, they want an immediate discount despite the higher historical price of inventory on hand.

Specialty performance grades do not move in lockstep with commodity prices.  Buyers are myopic about pricing and value of performance plastics if they only look at the latest CDI report.

Cost of goods sold - Steadily increasing higher resin costs put the squeeze on COGS & operating capital requirements.  Processors limited to only the increase of raw material costs find their cost of goods sold expressed as a percentage of sales ratcheting up at a frightening rate.  This is further exacerbated by inability to pass along other rising costs of doing business such as freight, power and health care.  It gets worse.  The same scrap rate with resin at triple the cost of 15 years ago erodes margins even further.

So what's the solution ?
One sure fire way to eliminate arguments over the price for polyethylene is to "toll" the resin.  This is a common practice.  The customer purchases the resin; the processor charges a lower rate since his capital is not employed.   Resin cars weigh 200,000 pounds so the math works out perfectly.  One car equals five truckloads of finished product.

Popular three year deals with quarterly adjustments do not benefit both parties as much as monthly adjustments.  Monthly adjustments allow optimizing of inventory levels to take advantage of the fluctuation of the price of PE resins.

Rather than focusing on the MSI, weight per part or price per pound, utilizing resins which are stronger gauge for gauge than commodity plastics results in a higher price per pound and lower price per part.  Specific to heat shrink films, reducing the amount of TD shrink to a consistent amount builds up to huge numbers.  Each percent of TD width is an equivalent % of savings.  Invoicing by net weight rather than gross weight saves money too.

Here is a link to every conversion factor you'll ever need for polyethylene films.  Try a few examples to see how fast a small reduction adds up:


LDPE film price

Read More

Topics: petroleum plastic, PE resin

Plastics in-depth and insights


Plastic Blogs

Subscribe by Email

Most Popular Posts

Browse by Tag