How to win in Polymer Engineering in 2025

Hello and welcome to the last past of 2024. Today I will share with you how to win in polymer engineering in 2025 using the following three steps: 

1. Define categories where you want to grow in Polymer Engineering - for example part design and material selection

2. Set objectives for each category, what you want to achieve in 2025 - for example: be able to systematically select the optimal plastic material for my part

3. Define quantifiable key results for each objective - for example: making a material selection example once a month by using examples from real life and literature

Happy new year and all the best for 2025! 

Greetings & #findoutaboutplastics

Herwig Juster

New to my Find Out About Plastics Blog - check out the start here section

🎤My Polymer Expert Talks Podcast

📹My YouTube channel

📚 My Polymer Material Selection book 

My personal website for polymer consulting

My dedicated site for Polymer Material Selection

Rule of Thumb in Polymer Engineering: How Economy of Scale Can Lower Costs

 Hello and welcome to this new Rule of Thumb post. More Rule of Thumbs can be found in my section "Start here". 

Economy of Scale: A Brief Explanation

Economy of scale refers to the cost advantage that arises when a company increases its production level. In simpler terms, the more a company produces, the lower the cost per unit becomes. This is because fixed costs (like rent, machinery, and salaries) are spread out over a larger number of units.

How Economy of Scale Can Lower Costs

• Increased Production Efficiency: Larger production runs often lead to more efficient processes, reducing waste and improving productivity (each time the cumulative production of a given product gets doubled, costs can be reduced in range of 15%).
• Bargaining Power with Suppliers: Larger companies can negotiate better deals with suppliers due to their increased purchasing volume.
• Specialized Equipment: Investing in specialized equipment can significantly reduce production costs for large-scale operations.
• Risk Diversification: Larger companies can better absorb market fluctuations and other risks.

Example: Plastic Injection Moulding

In plastic injection molding, economy of scale is a significant factor in determining production costs. A company that produces a large number of plastic parts can benefit from:

• Specialized Moulding Machines: High-volume production justifies the investment in advanced, efficient moulding machines that can produce parts faster and with less waste.
• Optimized Production Processes: With experience and scale, companies can fine-tune their production processes to minimize setup time, reduce cycle times, and improve quality. Using a Lang-factor of 0.75 we can reach a cost reduction of 30% when doubling the production amount (Figure 1).  
• Bulk Material Purchasing: Larger quantities of plastic resin can often be purchased at a discounted rate, reducing material costs.
• Efficient Manufacturing Layout: A well-designed manufacturing layout can streamline production flow, minimizing material handling and reducing overhead costs.

Figure 1: xample economy of scale in plastic injection moulding - doubling the production amount leads to a 30% cost reduction. 

By leveraging economy of scale, plastic injection moulding companies can significantly lower their production costs, making their products more competitive in the marketplace. 

Thanks for reading and #findoutaboutplastics

Greetings

Herwig Juster

Interested in my monthly blog posts – then subscribe here and receive my high performance polymers knowledge matrix.

New to my Find Out About Plastics Blog - check out the start here section

🎤My Polymer Expert Talks Podcast

📹My YouTube channel

📚 My Polymer Material Selection book 

My personal website for polymer consulting

My dedicated site for Polymer Material Selection

Literature:

[1] https://www.stratxsimulations.com/latest_materials_circular_markstrat/NetHelp/enu/Handbook-SM-B2C-DG/DocToHelpOutput/NetHelp/index.html#!Documents/productivitygains.htm

[2] https://www.voestalpine.com/highperformancemetals/en/blogposts/how-to-increase-efficiency-and-productivity-in-plastic-injection-molding/#

Plastic Multipoint Design Data: Specific Heat Capacity as a function of Temperature

Hello and welcome to a new blog post. Today I will show you another set of multipoint design data: specific heat capacity as a function of temperature. 

In a previous post I presented to you the Global Warming Potential (GWP) as a function of the heat capacity. However, the heat capacity values were limited to one temperature only (20°C). 

Increasing the temperature of a polymer by a dT at constant pressure is the result of a specific amount of heat supplied to the system. This is referred to as specific heat. 

Figure 1 presents the specific heat of amorphous and semi crystalline unfilled polymers. With increasing temperature the specific heat of both amorphous and semi crystalline polymers is increasing.

 

Figure 1: Specific heat capacity Cp as a function of temperature of amorphous and semi crystalline unfilled polymers.

There are several calculations in polymer engineering where the specific heat value of a certain polymer is needed: 

-calculation of the pressure drop along the gate or runner of an injection mould 

-dimensioning extrusion dies

-thermal design of moulds

-predicting the flow length of spiral melt flows

-polymer material selection for thermal management applications (thermal diffusivity)

Here you can find further design property data of various polymers for your part design and material selection. 

Thanks for your reading and #findoutaboutplastics

Greetings,

Herwig Juster

Interested to talk with me about your polymer material selection, sustainability, and part design needs - here you can contact me 

Subscribe to my Polymer Material Selection book launch page 

Interested in my monthly blog posts – then subscribe here and receive my high performance polymers knowledge matrix.

New to my Find Out About Plastics Blog – check out the start here section

My YouTube channel

Literature: 

[1] VDI Wärmeatlas

[2] Griesinger: Wärmemanagement in der Elektronik

[3] Natti: Design Formulas for Plastics Engineering 

Plastic Part Design Properties for Engineers - Water Uptake of Aliphatic Polyamides

Hello and welcome back to a new post. Today we discuss the water and moisture uptake of aliphatic short and long chain Polyamides. In a previous post I discussed the water uptake for high performance polymers - check it out here. Here you can find a collection of all my "Design Properties for Plastics Engineering" posts. 

Properties of Polyamides

In general, Polyamides are often used as engineering material due to their high thermal stability, very good strength and hardness, combined with high mechanical damping characteristics and good chemical resistance. However, all Polyamides are hygroscopic due to the polar amide groups which form hydrogen bonds with water. Water absorption (at a given temperature and relative humidity) is proportional to the amount of amorphous part of the Polyamide. As a consequence, the water acts as a plasticizer and lowers the mechanical properties. At higher temperatures, hydrolysis can take place too. 

How much is the water uptake of aliphatic Polyamides? 

Figure 1 shows the water uptake situation of the most used aliphatic Polyamides at equilibrium in 50% relative humidity and at equilibrium in complete saturation.

Figure 1: Water uptake data of most used aliphatic Polyamides

Long chain aliphatic Polyamides such as PA 6.10, PA 6.12, PA 11, and PA 12 show a lower water absorption compared to PA 6, PA 6.6, and PA 4.6.  Higher dimensional stability, together with low variation in the properties during ambient humidity changes are the result. Major reason for the lower water uptake is the relatively long hydrocarbon chain length (limiting the amide groups to form hydrogen bonds with water).

Important during material selection is the consideration of the  behavior of Polyamides when they are exposed to water (part immersion) or humid environment. The part dimensions need to be still kept within the specified tolerance. If a lower water uptake material with high dimensional stability compared to Polyamide, Polyketone can be a good alternative. Figure 2 compares the water absorption at saturation level of Polyamide PA 6.6 and Polyketone (23°C; weight-%). Polyketone reaches the saturation level at 2.1 % weight increase, where else PA 6.6 at 8.5 weight-%. 

Figure 2: Comparison water absorption of PA 6.6 and PK [4]. 

Thank you for reading and #findoutaboutplastics.

Greetings

Herwig Juster

🔥 There is a problem keeping you awake - My personal website for Polymer Consulting

📊 Discover your Polymer Material Selection score by taking quick test here

Literature: 

[1] https://www.findoutaboutplastics.com/2020/12/design-properties-for-engineers-water.html

[2] https://www.sciencedirect.com/science/article/pii/S2590048X20300911

[3] https://www.hanser-elibrary.com/doi/book/10.3139/9783446437296

[4] https://www.poketone.com/en/index.do

Carbonated PET Bottles - Saving Material by Optimization Calculation

PET bottle - Learn how to optimize the wall thickness

Hello and welcome to a new post. Today I will discuss with you how to optimize the wall thickness of well- known PET bottles by using safety factors and the stress equations.

What are some requirements for carbonated bottles?

In general, PET drink containers need to contain the pressure of dissolved C02 safely, easy processing via moulding / blow moulding, transparent or translucent, and must be recyclable. PET bottles are the cheapest solution to fulfill the aforementioned requirements. Next best alternative would be PLA which has the lowest embodied energy [1]. 

What equations do we need?

Figure 1 shows the internal pressure situation of a carbonated drink bottle. Tensile stresses along the walls are created  due to the internal pressure p inside the bottle. There are two stresses, the circumferential stress (𝛔c = pr/t) and the axial stress (𝛔a = pr/2t). t is the wall thickness and r is the radius of the bottle. Based on those, we can derive the must-have wall thickness so that the stresses are not leading to bottle failure: t= S [(pr)/(𝛔y)]. S is representing a safety factor and 𝛔y is the yield strength of the wall material. 

Figure 1: internal pressure situation of a carbonated drink bottle. 

Example: wall optimization of carbonated  PET bottle

In literature it can be found that the working pressure of a standard soda PET bottle is 0.5 MPa and has a diameter of 2r = 64 mm. As a safety factor we take 2.5. 70 MPa is the tensile strength of PET at room temperature. 

How thick do we need to make the walls to handle the pressure safely?

We start with our equation from before: t= S [(pr)/(𝛔y)]

t= 2.5 [(0.5x0.032)/(70)] = 0.00057 m = 0.57 mm

The required wall thickness t is 0.57 mm. After consuming your next soda drink in a PET bottle, you can check the wall thickness and see if the bottle already uses as little PET as possible. 

In another post I show how to select the optimal polymer material for an injection / blow moulded water bottle.

Thanks for reading and #findoutaboutplastics

Greetings, 

Herwig Juster

Interested to talk with me about your plastic selection, sustainability, and part design needs - here you can contact me 

Interested in my monthly blog posts – then subscribe here and receive my high performance polymers knowledge matrix.

New to my Find Out About Plastics Blog – check out the start here section

My YouTube channel

Literature:

[1] Michael Ashby: Materials and the Environment. Eco-informed Material Choice

Design Properties for Polymer Engineering: Dynamic Mechanical Analysis (DMA) of Unfilled Engineering Polymers

Hello and welcome to a new post. Today I present to you dynamic mechanical analysis (DMA) data of most used unfilled engineering polymers. 

In a previous post we discussed the storage modulus vs. temperature behavior of different high performance amorphous and semicrystalline polymers. Also how DMA can be used as a polymer material selection tool. Here you can find the collection of all my posts on design properties for plastics engineering - engineering and high performance polymers.

In general, the DMA is a thermo-analytical method that estimates the viscoelastic properties of a given material over the course of different temperatures. It steps away from a single point view toward a multipoint data view which is beneficial for polymer material selection tasks.

Figure 1 shows the elastic modulus of ABS, POM, PBT, and PA 6.6 and Figure 2 shows it for PMMA, POK, PC, and mPPE. Figure 3 contains all polymers in a single chart. 

Figure 1: Elastic modulus of ABS, POM, PBT, and PA 6.6 (all unfilled)

Figure 2: Elastic modulus of PMMA, POK,PC, and mPPE (all unfilled)

Figure 3: Elastic Modulus of ABS, POM, PBT, PA 6.6, PMMA, POK, PC, and mPPE.

Thanks for reading and #findoutaboutplastics

Greetings, 

Herwig

Interested to talk with me about your polymer material selection, sustainability, and part design needs - here you can contact me 

Interested in my monthly blog posts – then subscribe here and receive my high performance polymers knowledge matrix.

New to my Find Out About Plastics Blog – check out the start here section

My YouTube channel

My personal website

Literature: 

[1] M. Sepe: Dynamic Mechanical Analysis for Plastics Engineering, Elsevier

[2] https://www.findoutaboutplastics.com/2020/07/design-properties-for-engineers-dynamic.html

[3] https://www.findoutaboutplastics.com/2018/12/dynamic-mechanical-analysis-dma-as.html

Design Properties for Plastics Engineering: Key Electrical Properties of Selected Engineering and High Performance Polymers for E-Mobility

Hello and welcome to a new blog post. Today I present to you selected electrical properties of the most used engineering and high performance polymers. The data can support you during polymer material selection for various electric car applications.

In general, polymers in electric vehicles are used as isolators, insulators, and component housings and find many electrical focus applications such as busbars, connectors, circuit breakers, modules and switches that carry a current. At the same time, the demand for polymers is increasing in several property dimensions such as thermal rating, EMI shielding and thermal conductivity. Also, looking at autonomous driving systems, relative permittivity is a major concern and new plastic compounds are developed to offer solutions (low absorption or reflection of radar signals at 80 GHz [2]). In part design, we see more and more miniaturization resulting in a higher heat exposure to the polymer in use. Thinner walls represent another challenge for polymers to fill all the mould cavity.

In addition, environmental aspects play a key role in the use of plastics too. As already discussed in this post [3], the trinity of thermal, chemicals and time need to be considered since polymers change their behavior if exposed to chemicals and temperature.

Below the table shows the key electrical properties of selected engineering and high performance polymers for e-mobility. 

Key Electrical Properties of Selected Engineering and High Performance Polymers for E-Mobility 

Also, check out my training videos to better understand the individual properties: 

Polymers For E-Mobility I Electrical Design Properties I Part 1

Polymers For E-Mobility I Electrical Design Properties I Part 2 - Flammability Ratings

Polymers For E-Mobility I Electrical Design Properties I Part 3 - Comparative Tracking Indices (CTI)

Polymers For E-Mobility I Electrical Design Properties I Part 4 - Electromagnetic Interference (EMI)

Polymers For E-Mobility I Electrical Design Properties I Part 5 - Applications

Design Properties for Plastics Engineering - Engineering and High Performance Polymers (collection of all my posts)

Thanks for reading and #findoutaboutplastics

Greetings,

Herwig

Interested to talk with me about your plastic selection, sustainability, and part design needs - here you can contact me 

Interested in my monthly blog posts – then subscribe here and receive my high performance polymers knowledge matrix.

New to my Find Out About Plastics Blog – check out the start here section

My YouTube channel

Literature

[1] https://plastics.basf.com

[2] https://iopscience.iop.org/article/10.1088/2053-1591/abcb3b/pdf

[3] https://www.findoutaboutplastics.com/2020/11/plastic-part-failure-part-2-antidote.html

[4] https://www.findoutaboutplastics.com/2020/10/design-properties-for-engineers.html

Design Properties for Engineers: Water and Moisture Absorption of High Performance Polymers

Design Properties for Engineers: Water and Moisture Absorption of High Performance Polymers

In this blog post, we discuss the water and moisture of high performance polymers.

Important for material selection is the behavior of polymer compounds when they are exposed to water (part immersion) or humid environment. Contact of plastics with water and humidity is possible; however water can diffuse into the plastic and change its physical and dimensional properties. This is depending on the contact time and geometry of the plastic part.

Depending on the polymer, water remains on the surface or it diffuses into the polymer. Diffusion lowers the inter-molecular binding forces and in turn increases the chain mobility. As a consequence, mechanical strength is reduced. Furthermore, electrical and other physical properties are reduced too. Also, dimensional changes occur. Polymers which show a strong volume change (high diffusion rate) are called hygroscopic.

The good message is that most of those processes are physical nature and are reversible by applying a proper drying process. However, when polymers are often exposed to water vapor, the risk of hydrolysis (=chemical reaction in which water molecules rupture one or more chemical bonds and can lead to chain breakage) is much higher compared to normal water exposure.

Measurement standards

Classification of water and moisture uptake is done by using ISO 62 (water absorption 24 hours, 23°C) and/or ASTM D570.

Low water uptake

Among the high performance polymers, fluoropolymers such as PTFE and PVDF take up very low amounts of water. The same is valid for Polyphenylene Sulfide (PPS). Polysulfones (PSU, PESU, PPSU) take up a limited amount of water. Polyarylketones (PEEK, PEK, PEKEKK) absorb low amounts of water too.  Hydrolysis resistance of the aforementioned materials is outstanding. Water vapor sterilization is several times possible without compromising on the properties.

Hygroscopic high performance polymers

On the other hand, Polyimides are hydroscopic. They take up high amounts of water already in normal climate conditions (50% humidity in air). Direct contact with water results in even more water uptake (e.g. PBI: 14%). Hydrolysis resistance is lower compared to PEEK or PPS and as a result cracks are formed over time when exposed to water. If the plastic part is wet and will be rapidly heated (in case of high temperature applications), expansion of water turning into vapor can cause damage to the part.

A small water uptake of PAI is influencing the physical properties immediately: elongation increases more than 10% at 2% water uptake. Impact strength increases 20% compared to the starting point. Sometimes, changes due to water uptake can be an advantage too. There are lots of parts which need to be mounted and in such cases it is beneficial to have more elongation due to water uptake compared to a dry part.

Polyphthalamide (PPA), especially PA6T/6I and long chain PPA (PA9T and PA10T) show much lower water and moisture uptake compared to aliphatic polyamides. 

A word on moisture uptake and dimensional changes after moulding 

Moisture absorption begins in the moment the part leaves the mould (in particular for hygroscopic materials).

As moulded, the moisture content of the part is approximately equal to that of the pellets that went into the moulding machine. Let us assume that e.g. an aliphatic Polyamide such as PA 6.6 is properly dried before moulding, this would place the moisture content for a part produced from unfilled PA 6.6 below 0.20% (referred to as dry-as-moulded).

Water molecules force the polymer chains to increase and this leads to volumetric expansion. The part size increase can be equal to 0.5-0.6% in an unfilled PA 6.6 (at room temperature; higher temperatures results in higher changes). However, glass fiber reinforced compounds can reduce the dimensional changes down to 0.1%.

Thanks and #findoutaboutplastics

Greetings,

Herwig

Interested in my monthly blog posts – then subscribe here and receive my high performance polymers knowledge matrix.

New to my Find Out About Plastics Blog – check out the start here section

Polymer Material Selection (PoMS) - check out my new online course

Enroll here for watching the free parts of the course

Literature:

[1] Erwin Baur, Tim A. Osswald, Natalie Rudolph: Saechtling Kunststoff Taschenbuch, Hanser Munich 

[2] https://www.ptonline.com/articles/dimensional-stability-after-molding-part-4

 

Plastics Part Design: Coefficient of Linear Thermal Expansion (CLTE) of 136 Polymers

Topic of this blog post is the coefficient of linear thermal expansion (CLTE).

CLTE is often presented with the letter “α” and is calculated using the following equation:

α = ΔL / (L0 * ΔT).

L0 is the length of the part at room temperature; ΔL is the length variation of the specimen when it is heated up, and ΔT is the temperature difference between start and end. More details can be found in the standard ASTM D696.

Polymers in applications such as bus bars, which are used in traction motors, battery modules and power electronics, need to pass thermal shock tests. In such tests, metal bars are overmoulded. Thermal cycles between -40°C (1 hour) and +150°C (1 hour) of the overmoulded bars are done. The cycles are counted until cracking of the polymer layer occurs. The similar the CTLE value of both materials and the better the elongation at break of the overmoulded polymer are, the easier the selected material will pass such tests.

In the table below you can find the maximum CLTE of 136 polymers. Furthermore, I added a factor which shows how similar the polymer is to copper in terms of thermal expansion. This is useful for overmoulding of copper elements.



You can add this table to your part design library. Here, you can find some more part design related data: continuous use temperature and thermal conductivity.

Thanks for reading & till next time!

Greetings,
Herwig Juster

Literature:
[1] https://omnexus.specialchem.com/polymer-properties/properties/coefficient-of-linear-thermal-expansion

Polymer densities: "You know your're a plastics engineer if..."

...you know the specific density of most polymers without having to look it up."

Still, having a repository of 318 polymers with their specific density at hand can help you in certain material selection decisions.

Enjoy the table and thanks for reading!

Thanks to Scientific Polymer Products for the data.

Greetings, Herwig

P.S. New to my blog - check out the start here section.

  

Chemical Name	Density (g/cc)
Poly(4-methyl-1-pentene)	0,83
Poly(1-pentene)	0,85
Ethylene/propylene/diene terpolymer-50% ethylene/4% diene	0,86
Ethylene/propylene copolymer-60% ethylene	0,86
Poly(1-butene)	0,86
Poly(1-hexene)	0,86
Poly(1-octadecene)	0,86
Polypropylene, atactic	0,866
Polymethylhexadecylsiloxane	0,88
Polymethyltetradecylsiloxane	0,88
Ethylene/butylene copolymer, dihydroxy terminated	0,88
Ethylene/butylene copolymer, monohydroxyl terminated	0,88
Poly(vinyl n-decyl ether)	0,883
Polymethyloctadecylsiloxane	0,886
Poly(1,4-pentadiene)	0,89
Poly(methyl n-tetradecyl siloxane)	0,89
Poly(methyl n-octadecylsiloxane)	0,89
Poly(vinyl n-dodecyl ether)	0,892
Poly(1,4-butadiene)	0,892
Polypropylene, isotactic	0,9
Polybutadiene, cis	0,9
Polybutadiene, cis & trans-36% trans	0,9
Poly(vinyl 2-ethylhexyl ether)	0,904
Polyisoprene	0,906
Polybutadiene, dicarboxy terminated	0,907
Poly(1,2-butadiene)	0,909
Polymethylhexylsiloxane	0,91
Styrene/ethylene-butylene, ABA block copolymer-29% styrene	0,91
Polydimethylsilane	0,91
Polybutadiene oligomer, acrylated	0,91
Polymethyloctylsiloxane	0,91
Poly(methyl n-octylsiloxane)	0,91
Styrene/butadiene copolymer-5% styrene	0,91
Poly(methyl n-hexylsiloxane)	0,91
Poly(vinyl n-octyl ether)	0,914
Poly(1-butene), isotactic	0,915
Styrene/isoprene, ABA block copolymer-14% styrene	0,92
Polyisobutylene	0,92
Poly(isobutylene-co-isoprene)-2.2% isoprene	0,92
Polyethylene, low density	0,92
Poly(vinyl sec-butyl ether)	0,92
Poly(vinyl isopropyl ether)	0,924
Poly(butadiene-co-acrylonitrile), dicarboxy terminated-10% acrylonitrile	0,924
Ethylene/vinyl acetate copolymer-18% vinyl acetate	0,925
Poly(vinyl n-hexyl ether)	0,925
Poly(vinyl n-butyl ether)	0,927
Ethylene/vinyl acetate copolymer-9% vinyl acetate	0,928
Poly(lauryl methacrylate)	0,929
Poly(dodecyl methacrylate)	0,929
Poly(isobutylene-co-isoprene), brominated-1,5% isoprene, 2.1% bromine	0,93
Polyethylene, oxidized	0,93
Ethylene/acrylic acid copolymer-5% acrylic acid	0,93
Ethylene/ethyl acrylate copolymer-18% ethyl acrylate	0,93
Polybutadiene, phenyl terminated	0,93
Poly(vinyl isobutyl ether)	0,93
Ethylene/vinyl acetate copolymer-14% vinyl acetate	0,932
Styrene/butadiene copolymer-23% styrene	0,935
Poly(butadiene-co-acrylonitrile), amine terminated-10% acrylonitrile	0,938
Styrene/butadiene, ABA block copolymer	0,94
Polydimethylsiloxane, ethoxy terminated	0,94
Ethylene/vinyl acetate copolymer-25% vinyl acetate	0,948
Polyethylene, high density	0,95
Ethylene/methacrylic acid ionomer, sodium ion	0,95
Poly(p-t-butyl styrene)	0,95
Poly(vinyl ethyl ether)	0,95
Poly(vinyl cyclohexane)	0,95
Ethylene/methacrylic acid ionomer, zinc ion	0,95
Ethylene/vinyl acetate copolymer-28% vinyl acetate	0,951
Ethylene/vinyl acetate copolymer-33% vinyl acetate	0,952
Poly(butadiene-co-acrylonitrile), dicarboxy terminated-18% acrylonitrile	0,955
N-Vinylpyrrolidone/vinyl acetate copolymer-30% N-vinyl pyrrolidone	0,955
Poly(butadiene-co-acrylonitrile), amine terminated-16.5% acrylonitrile	0,956
Poly(butadiene-co-acrylonitrile), dicarboxy terminated-21.5% acrylonitrile	0,958
Polyisoprene, trans	0,96
Poly(butadiene-co-acrylonitrile), dicarboxy terminated-26% acrylonitrile	0,96
Poly(methyl vinyl ether/maleic acid), monobutyl ester	0,962
Styrene/butadiene copolymer-45% styrene	0,965
Octadecene-1-maleic anhydride copolymer-20% maleic anhydride	0,97
Acrylonitrile/butadiene copolymer-22% acrylonitrile	0,97
Acrylonitrile/butadiene copolymer-21% acrylonitrile	0,97
Acrylonitrile/butadiene copolymer-29% acrylonitrile	0,97
Polydimethylsiloxane	0,97
Poly(n-octyl methacrylate)	0,971
Poly(tetramethylene ether) glycol	0,979
Ethylene/vinyl acetate copolymer-40% vinyl acetate	0,98
Ethylene/vinyl acetate copolymer-45% vinyl acetate	0,98
Polydimethylsiloxane, dihydroxy terminated	0,98
Polydimethylsiloxane, dimethylamine terminated	0,98
Polydimethylsiloxane, acetoxy terminated	0,98
Poly(propylene oxide), monoamine terminated	0,98
Acrylonitrile/butadiene copolymer-33% acrylonitrile	0,98
Poly(vinyl n-butyl sulfide)	0,98
Poly(vinylmethylsiloxane)	0,98
Polyoxytetramethylene	0,98
Poly(butadiene-co-acrylonitrile), vinyl terminated-16% acrylonitrile	0,985
Acrylonitrile/butadiene copolymer-38% acrylonitrile	0,99
Acrylonitrile/butadiene copolymer-27% acrylonitrile	0,99
Acrylonitrile/butadiene copolymer-45% acrylonitrile	0,99
Ethylene/vinyl acetate copolymer-50% vinyl acetate	0,99
Acrylonitrile/butadiene copolymer-31% acrylonitrile	0,99
Acrylonitrile/butadiene copolymer-44% acrylonitrile	0,99
Polymethylhydrosiloxane	0,99
Poly(1,2,2-trimethylpropyl methacrylate)	0,991
Poly(neopentyl methacrylate)	0,993
Poly(propylene oxide), diamine terminated	0,9964
Poly(propylene oxide), diurea terminated	0,9989
Poly(vinyl stearate)	1
Polydimethylsiloxane, chlorine terminated	1
Acrylonitrile/butadiene copolymer-43% acrylonitrile	1
Acrylonitrile/butadiene copolymer-51% acrylonitrile	1
Acrylonitrile/butadiene copolymer-41% acrylonitrile	1
Poly(propylene oxide)	1
Poly(t-butyl acrylate)	1
Poly(3,3-dimethylbutyl methacrylate)	1,001
Poly(propylene oxide), triamine terminated	1,003
Poly(propylene glycol)	1,005
Poly(1,3-dimethylbutyl methacrylate)	1,005
Poly(n-hexyl methacrylate)	1,007
Poly(dimethylsiloxane-co-ethylene oxide), AB block-25% dimethylsiloxane	1,007
Nylon 12 [Poly(lauryllactam)]	1,01
Poly(1-methylpentyl methacrylate)	1,013
Poly(1,4-butylene adipate)	1,019
Poly(vinyl propionate)	1,02
Poly(t-butyl methacrylate)	1,022
Poly(o-methyl styrene)	1,027
Poly(1-methylbutyl methacrylate)	1,03
Poly(isopentyl methacrylate)	1,032
Poly(n,n-dimethyl-3,5-dimethylene piperidinium chloride)	1,033
Poly(isopropyl methacrylate)	1,033
Poly(4-methylstyrene), monocarboxy terminated	1,04
Poly(4-methylstyrene)	1,04
Nylon 11 [Poly(undecanoamide)]	1,04
Poly(2-ethylbutyl methacrylate)	1,04
Poly(vinyl n-pentyl ether)	1,041
Poly(isobutyl methacrylate)	1,045
Poly(dimethysiloxane-co-diphenylsiloxane)-80% dimethylsiloxane	1,05
Polystyrene, monomethacrylate terminated	1,05
Polystyrene, monohydroxy terminated	1,05
Poly(vinyl methyl ether)	1,05
Polystyrene, 90% syndiotactic	1,05
Polystyrene	1,05
Poly(5-phenyl-1-pentene)	1,05
Poly(sec-butyl methacrylate)	1,052
Poly(n-butyl methacrylate)	1,055
Polyethyleneimine, epichlorohydrin modified	1,055
Polydiethoxysiloxane	1,06
Ethylene/vinyl acetate copolymer-70% vinyl acetate	1,06
Poly(2,6-dimethyl-p-phenylene oxide)	1,06
Poly(isobutyl acrylate)	1,06
Poly(isobornyl methacrylate)	1,06
Polyphenylene oxide	1,06
Poly(dimethylsiloxane-co-ethylene oxide), AB block-18% dimethylsiloxane	1,066
Poly(dimethylamine-co-epichlorohydrin), quaternized	1,07
Nylon 6/12 [Poly(hexamethylene dodecanediamide)]	1,07
Poly(diethylene triamine-co-adipic acid)	1,07
Polyethyleneimine	1,07
Poly(caprolatone)diol	1,07
Poly(caprolatone)triol	1,073
Poly(alpha-methylstyrene)	1,075
Nylon 6/9 [Poly(hexamethylene nonanediamide)]	1,08
Poly(ethylene oxide), diamine terminated	1,08
Poly(isopropyl acrylate)	1,08
Polyethyleneimine, 80% ethoxylated	1,08
Poly(n-propyl methacrylate)	1,08
Styrene/acrylonitrile copolymer-25% acrylonitrile	1,08
Nylon 6/10 [Poly(hexamethylene sebacamide)]	1,08
Nylon 6/6 [Poly(hexamethylene adipamide)]	1,08
Styrene/allyl alcohol copolymer-6% hydroxyl	1,083
Poly(vinyl butyral)-11% hydroxyl content	1,083
Poly(vinyl butyral)	1,083
Poly[2,2-propane bis[4-(2,6-dimethylphenyl)]carbonate]	1,083
Poly(ethylene sebacate)	1,085
Poly(n-butyl acrylate)	1,087
Butyl methacrylate/isobutyl methacrylate copolymer-50/50 copolymer	1,09
Poly(methyl m-chlorophenylethylsiloxane)	1,09
Poly(alpha,alpha-dimethylpropiolactone)	1,097
Poly(ethylene glycol mono-methyl ether)	1,097
Polystyrene sulfonic acid	1,1
Polyethylene, chlorinated-25% chlorine	1,1
Polysulfone, anionic	1,1
Polymethacrylonitrile	1,1
Poly(cyclohexyl methacrylate)	1,1
Poly(methyl m-chlorophenylsiloxane)	1,1
Poly(vinyl butyral)-19% hydroxyl content	1,1
Poly(ethyl methacrylate)	1,11
Polymethylphenylsiloxane	1,11
Poly(methylphenylsiloxane)	1,11
Poly(acryloxypropylmethylsilane)	1,11
Poly(p-cyclohexylphenyl methacrylate)	1,115
Vinyl alcohol/vinyl butyral copolymer-80% vinyl butyral	1,12
Nylon 6(3)T [Poly(trimethyl hexamethylene terephthalamide)]	1,12
Poly(vinyl methyl ketone)	1,12
Nylon 6 [Poly(caprolactam)]	1,12
Poly(ethyl acrylate)	1,12
Poly(2,2,2′-trimethylhexamethylene terephthalamide)	1,12
Poly(1-phenylethyl methacrylate)	1,129
Poly(2-ethyl-2-oxazoline)	1,14
Ethyl cellulose	1,14
Poly(2,6-diphenyl-1,4-phenylene oxide)	1,14
Polycaprolactone	1,143
Poly(1,2-diphenylethyl methacrylate)	1,147
Poly(t-butylaminoethyl methacrylate)	1,15
Poly(2-hydroxyethyl methacrylate)	1,15
Poly(styrene oxide)	1,15
Polyethylene, chlorinated-36% chlorine	1,16
Poly(diphenylmethyl methacrylate)	1,168
Poly(ethylene succinate)	1,175
Poly(benzyl methacrylate)	1,179
Styrene/maleic anhydride copolymer-75% styrene	1,18
Phenoxy resin	1,18
Poly(vinyl methyl sulfide)	1,18
Poly(methacrylic acid), sodium salt	1,18
Poly(ethylene adipate)	1,183
Poly(ethylene azelate)	1,183
Polyacrylonitrile	1,184
Poly(vinyl acetate)	1,19
Poly(1,4-cyclohexylidene dimethylene terephthalate)	1,196
Polydiphenoxyphosphazene	1,2
Poly(methyl methacrylate)	1,2
Poly(n-vinyl carbazole)	1,2
Polycarbonate	1,2
Bisphenol A polycarbonate	1,2
Poly[1,1-(1-phenylethane) bis(4-phenyl)carbonate]	1,2
Poly(ethylene glycol)	1,207
Poly(methylene-co-guanidine), hydrochloride	1,21
Poly(ethylene-co-chlorotrifluoroethylene)	1,21
Poly(phenyl methacrylate)	1,21
Poly(ethylene oxide)	1,21
Polyethylene, chlorinated-42% chlorine	1,22
Poly(methyl acrylate)	1,22
Polyimidazoline, quaternized	1,22
Polychloroprene	1,23
Cellulose propionate	1,23
Poly(vinyl formal)	1,23
Poly(methylene[polyphenyl isocyanate)]	1,24
Polysulfone	1,24
Poly[4,4′-isopropylidene diphenoxy di(4-phenylene)sulfone]	1,24
Poly(sec-butyl alpha-chloroacrylate)	1,24
Poly[methane bis(4-phenyl)carbonate]	1,24
Poly(n-butyl alpha-chloroacrylate)	1,24
Polyethylene, chlorinated-48% chlorine	1,25
Zein, purified	1,25
Polyoxymethylene	1,25
Poly(N-vinyl pyrrolidone)	1,25
Poly(cyclohexyl a-chloroacrylate)	1,25
Poly(diallyl isophthalate)	1,256
Cellulose acetate butyrate	1,26
Poly(diallyl phthalate)	1,267
Poly(tetramethylene isophthalate)	1,268
Poly[1-(o-chlorophenyl)ethyl methacrylate]	1,269
Polysulfide rubber	1,27
Styrene/maleic anhydride copolymer-50% styrene	1,27
Poly(isopropyl a-chloroacrylate)	1,27
Polyethylene, chlorosulfonated	1,28
Poly(vinyl alcohol)	1,29
Poly(n-propyl a-chloroacrylate)	1,3
Poly(methyl y-trifluoropropylsiloxane)	1,3
Poly[2,2′-(m-phenylene)-5,5′-bibenzimidazole]	1,3
Polyacrylamide	1,302
Poly(methyl alpha-cyanoacrylate)	1,304
Polybutadiene terephthalate	1,31
Cellulose acetate	1,31
Cellulose triacetate	1,31
Poly(2-chloroethyl methacrylate)	1,32
Poly(m-trifluoromethylstyrene)	1,32
Vinyl chloride/vinyl acetate copolymer-81% vinyl chloride	1,33
Poly(ethylene-2,6-naphthalenedicarboxylate)	1,33
Poly(ethylene phthalate)	1,338
Poly(ethylene isophthalate)	1,34
Poly(2,2,2-trifluoro-1-methylethyl methacrylate)	1,34
Vinyl chloride/vinyl acetate copolymer, carboxylated	1,35
Poly[thio bis(4-phenyl)carbonate]	1,355
Polyepichlorohydrin	1,36
Vinyl chloride/vinyl acetate copolymer-90% vinyl chloride	1,36
Poly(phenylene sulfide)	1,36
Poly(B-propiolactone)	1,36
Vinyl chloride/vinyl acetate copolymer-88% vinyl chloride	1,37
Methyl vinyl ether/maleic anhydride copolymer-50/50 copolymer	1,37
Poly(p-phenylene ether-sulphone)	1,37
Poly(3-chloropropylene oxide)	1,37
Poly(vinyl fluoride)	1,38
Poly(ethylene terephthalate)	1,385
Hydroxyethyl cellulose	1,39
Hydroxypropyl methyl cellulose	1,39
Vinyl chloride/vinyl acetate/vinyl alcohol terpolymer-91% vinyl chloride, 3% vinyl acetate	1,39
Poly(vinyl chloride), carboxylated	1,39
Methyl cellulose	1,39
Poly(ethyl a-chloroacrylate)	1,39
Polyimide	1,4
Poly(vinyl chloride)	1,4
Poly(acrylic acid)	1,41
Vinylidene chloride/vinyl chloride copolymer-5% vinyl chloride	1,41
Poly[2,2-propane bis[4-(2,6-dichlorophenyl)]carbonate]	1,415
Polyacetal	1,42
Poly[N,N’-(p,p’-oxydiphenylene)pyromellitimide]	1,42
Poly(4-fluoro-2-trifluoromethylstyrene)	1,43
Poly(p-hydroxy benzoate)	1,44
Poly(p-oxybenzoate)	1,44
Melamine cellulose	1.45-1.52
Poly(vinyl chloroacetate)	1,45
Melamine formaldehyde	1,48
Poly(3,3,3-trifluoroethylene)	1,58
Alginic acid, sodium salt (algin)	1,59
Cellulose nitrate	1,6
Poly(glycolic acid)	1,6
Polyisoprene, chlorinated	1,63
Vinylidene chloride/acrylonitrile copolymer-20% acrylonitrile	1,65
Poly(vinylidene chloride)	1,66
Poly(vinylidene fluoride)	1,76
Poly(hexafluoropropylene oxide)	1,91
Polychlorotrifluoroethylene	1,92
Poly[2,2-propane bis(4-(2,6-dibromophenyl)]carbonate]	1,953
Nafion 117, hydrogen ion form	1,98
Poly[2,2-hexafluoropropane bis[4-(2,6-dibromophenyl) carbonate]	1,987
Melamine	2
Phenolic resins	2
Poly(tetrafluoroethylene)	2
Poly(2,4,6-tribromostyrene)	2,1
Poly[tetrafluoroethylene-co-perfluoro(alkyl vinyl ether)]	2,15
Source: http://scientificpolymer.com/density-of-polymers-by-density/