As I mentioned in a recent post, after a number of years of searching, I finally found a copy of the Plastics Materials Digest – International Plastics Selector. Before the internet, when I needed to find a material or look up properties, this is how I did it.
The books contain thousands of property data sheets as well an index that allows you to look up materials by trade name and even physical properties.These books were very good. If you needed a polypropylene with tensile strength over 3600 psi, you could find it in the index and then it would refer you to the page where you could find the full data sheet.
The copy that I found happened to be from 1988, the same year that I started in the industry.
I have had a little time to look through the book now and I have a few observations.
1. There is only one grade of low gloss ABS listed.
Lustran LGA is listed in the book but other grades like Magnum 342 do not exist yet in 1988. Low gloss ABS was developed primarily for the auto industry. Automotive designers were looking for lower gloss materials for interior parts and the plastics industry answered this demand with low gloss ABS. This was just beginning in 1988.
Low gloss ABS typically has lower impact than higher gloss grades, however, the data sheet for the LGA shows a 6 ft-lb/in (320 J/m) izod impact which is very high. The current data sheet shows an impact of 3.2 ft-lb/in (170 J/m).
It is also interesting to note that there are no Samsung or LG ABS materials listed. If they were making ABS back then, they were not selling it in the US.
2. Polypropylene properties have not changed.
Many people claim that polypropylene copolymer and homopolymer are not as strong they used to be. There has been some changes in polypropylene manufacturing in recent years which many people think has changed the tensile strength for the worse.
If this has happened, the data sheets do not show it. There are just as many grades of homopolymer with tensile strength above 5500 psi (37.9 Mpa) now as there was in 1988. There are just as many copolymers with tensile strength over 3500 psi (24.1 Mpa) now as in 1988 also.
3. Chemical coupling of polypropylene glass filled has dramatically improved tensile strength.
A survey of several grades of PP Homo 30% Glass Coupled reveals that there has been very little change in tensile strength since 1988. Thermofil’s Thermylene P6-30FG-0100 shows 12,000 psi (82.8 Mpa) in 1988. That exact grade is not made any longer but the P6-30FG-0632 grade shows a tensile strength of 12,200 psi (84.1 Mpa). Not a significant change.
4. TPO was in its infancy in 1988.
I counted 111 grades of TPO that were listed in 1988. Today, there are over 600 grades listed on Prospector. The Material Selector refers to TPO as Polyolefin. There is no TPO section.
The first TPO bumper fascia was on the 1985 Chevrolet Cavalier. Over the next 20 years TPO would come to dominate the bumper fascia industry but 1988 was just the beginning.
5. PPE and PPO are listed as different materials.
Polyphenylene Oxide (PPO) and Polyphenylene Ether (PPE) are the same material expressed in two different ways. Compounds containing oxygen are often described as ethers in Europe. In the 1988 book the Noryl materials are listed as PPO and the Borg Warner Prevex materials are listed PPE. GE might have had some type of trademark on the PPO designation. Borg-Warner sold their plastics division to GE in the 1990s and the Prevex brand was retired.
I notice now that Prospector shows these grades as alloys. Either PPE-PS or PPE-PA depending on the grade.
6. One of the biggest producers of polypropylene was a company called Rexene.
Rexene was absorbed into Huntsman in 1997.
7. Santoprene was made by Monsanto.
The Santoprene brand has changed hands a number of times over the years but I did not remember that it was part of Monsanto at one time.
The International Plastics Selector is a great addition to my small but growing collection of plastics industry memorabilia. I was really happy to find it and I have enjoyed thumbing through it.