Thursday, 21 October 2021

Guest Interview: Paolo Negri – Founder and Owner of Isotattica “Stop turning the knobs and apply hands-on rheology to troubleshoot and design your materials and equipment!”

Hello and welcome to this guest interview. Today I present to you Mr. Paolo Negri founder and owner of Isotattica. We have the chance to learn about analysis on polymer flow behaviour with innovative methods.

Enjoy the interview!

Tell us about yourself, your current role, and about Isotattica.

Thank you for having me on your blog. I am Paolo Negri founder and owner of Isotattica.

I have always worked in the fantastic world of polymers and I am driven by the passion of offering innovative service with multidisciplinary approach.

My Vision is to become a valuable reference for industrial rheology with innovative methods to be used with concrete problem-solving purpose.

With over 25 + years of transversal activities in the field of polymers, extrusion, rheometry, we provide technical support to solve problems that arise during processing phase of the materials, with strong focus on rheology as methodology and “tool” to elucidate and optimize processes and equipment.

What is the rheological investigation method and device you developed and what is the practical usage of it?

Rheology is concerned with measuring the stress in a material and relating it to its deformation in the molten flow of the material.

Rheology is still little known in the industrial field because it is considered complex, of impractical implementation and does not bring practical results, vice versa I want to propose a different way of utilization of it: if findings are expressed in an understandable reading and applied in a pragmatic and concrete way to industrial processes, rheology becomes a valid approach to understand and resolve critical issues.

Understanding the flow properties of polymers through tests directly on extrusion-connected equipment can help optimize products and process conditions, thus saving costs and minimizing potential waste.

My motto is: Stop turning the knobs and apply hands-on rheology to troubleshoot and design your materials and equipment!

Isotattica offers analysis on flow behaviour with innovative methods: flow visualization and rheometric measurement through flow-induce birefringence and elongational experiments made with a filament stretching apparatus.

The first approach is innovative (the optical cell is patent pending) and allows flow visualization and mapping of stresses and deformation inside the geometry of flow channels. Thanks to the so called “optical rule” is it possible to sequence and calculate stresses and finally to determine viscosity in the melt stream where elongational specifically takes place.

The second approach, filament-stretching-method, is mainly used as complementary test and allows assessment of the melt quality in extensional experiments.

I invite readers to learn more on my website

What are some potential applications?

The proposed methods of analysis are very sensitive: it is possible to replicate industrial process condition and capture the details that explain the difference in extrudability, for example due to the smallest of batch fluctuation;

In addition, it is possible to understand the contribution of elongational deformation in “complex flow” and correlate structure-property-processing-performance.

Die designers benefit from this because they can finally size the channels paths and tooling’s based on the specific and well understood flow responses of the materials and not based on generic data.

Where can the readers find out more about you and the services of Isotattica?

Whatever you would like to know about Isotattica including practical examples of utilization of these analysis, you can visit our website or simply mail or call me asking to provide specific details and offers.

With the pandemic continuing, we are more enhancing on in-direct communication via video conferences.

Who do you turn to?

We provide concrete and pragmatic support:

- To those who need to design new materials / compounds and perform rheometric characterizations for mapping and quantifying flow response, with emphasis in the extensional field in the various channel’s geometries or in downstream operation like blowing, cast film, profile extrusions, strand palettization, injection molding and many others

- To those who need to design and manufacture process equipment and layouts (co-extrusion heads / dies, extruders, downstream equipment) for specific industrial applications where knowledge of the shear characteristics but above all in elongation are vital.

- Who must study the extrusion process and its efficiency based on the rheological response of the materials and their stability when changing extrusion settings.

- To producers and converter of materials, or to deepen the intimate rheological aspects that cannot be captured with conventional approaches and that can make the difference.

- To those who need material consultation, for proper material selection, design review, feasibility study.

- To those who want to acquire mastery in dealing with and solving problems and improve business by distinguishing themselves from competitors.

That was the guest interview with Paolo Negri from Isotattica – thank you Paolo for the interesting insights into the polymer rheology world!

Greetings and #findoutaboutplastics

Herwig Juster

#rheology #guestinterview #Isotattica

Interested to talk with me about your plastic selection 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
You can support me here on  PayPalMe
Polymer Material Selection (PoMS) for Electric Vehicles (xEVs) - check out my new online course

Monday, 11 October 2021

Bio-Based Polyamides – Part 2: Short and Long Chain Aliphatic Polyamides (PA 6, PA 11, PA 6.10, PA 10.10)

Hello and welcome back to our bio-based polyamide blog series. In part 1 we discussed the bio-based PA 5.6 and today in part 2 we discuss bio-based homopolyamides (short and long chain) as well as long chain copolyamides (polyalkylene sebacamides).

Homopolyamides from Biomass Derived Monomers

There are two commercially feasible ways in making biomass based Polyamide 6 (Figure 1): the first route is over sugar and the second route uses starch as a starting point. In the second route an additional processing step is needed (hydrolysis of starch to obtain Glucose). For obtaining a long chain homopolyamide (PA 11), five processing steps are involved and 93% more biomass is needed to obtain 1 metric ton of Polyamide. AS a starting point for Bio-PA 11, caster beans are used.

Figure 1: Routes for making Bio-PA6 and Bio-PA 11

Copolyamides from Biomass Derived Monomers

For obtaining a long chain biomass based copolyamide we need a diamine which reacts with a diacid and either both (fully bio-based) or just one (partially bio-based) is derived from biomass. In Figure 2, the reaction routes of Bio-PA 6.10 and Bio-PA 10.10 are shown.

Figure 2: Routes for making Bio-PA 6.10 and Bio-PA 10.10

Selected properties of bio-based polyamides

In Table 1, typical properties of petroleum-based and bio-based polyamides are shown. The functional amide group which facilitates an internal hydrogen bond between the polymer chains, leads to properties such as hardness, good impact strength and excellent abrasion resistance. Comparing short chain to long chain aliphatic polyamides, the short chain outperforms the long chain in terms of thermal and mechanical properties. However, the long chain aliphatic polyamides have a higher chemical resistance as well as hydrolysis resistance together with low water uptake. Bio-based Polyamides cover the short chain and long chain spectra and depending on the application case, they can outperform or underperform petrol-based Polyamides. The properties shown in Table 1 are the base polymer properties and in most cases the base polymer will be modified with glass fibers and additives. This in turn will make direct comparisons more difficult and more data must be considered in the polymer material selectionprocess (long term data, cyclic data, and chemical data).  

Table 1: Selected properties of petrol- and bio-based Polyamides

Processing and Applications

Injection moulding polyamides represents around 76% of the total polyamide consumption and the automotive and truck market is here in the lead in terms of annual consumption. Other important markets are consumer articles, electrical and electronic parts and appliances parts. Extrusion represents 23% of the total polyamide consumption and covers applications in the field of wire and cable, tubing and piping, and non textile filaments. The remaining 1 % represents powder coating applications.

Bio-based Polyamides start to capture applications in the automotive field, especially for Electric Vehicles. However, due to the current price level and capacities, Automotive will not be the dominating applications field. Long chain bio-based Polyamides offer different properties compared to the more price sensitive short chain Polyamides. Blending and co-polycondensation with petrol based Polyamides will allow to reach the ideal price-to-performance ratio faster. Ongoing regulations to reach certain CO2 levels and Global Warming Potentials (GWP) allows bio-based Polyamides to faster capture applications in different industry sectors. Also, customer demand for such solutions is increasing as well as the regulations.

Thank you for reading and #findoutaboutplastics


Herwig Juster

#materialselection #polymerengineering #biobased #biopolyamides

Interested to talk with me about your plastic selection 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
You can support me here on  PayPalMe
Polymer Material Selection (PoMS) for Electric Vehicles (xEVs) - check out my new online course





[4] Bio-Based Plastics Materials and Applications, S. Kabasci;