Webinar

How Many Tie Chains are Needed for a Semicrystalline Polymer to be Ductile?

Prof. Richard A. Register

Department of Chemical and Biological Engineering 

and Princeton Materials Institute,

Princeton University

Wednesday, August 19,   Webinar at 6:00 PM Pacific time

Abstract

Semicrystalline polymers of low glass transition temperature, such as polyethylene (PE) and hydrogenated polynorbornene (hPN), can be either brittle or ductile depending on how well stress can be transmitted between crystallites—such as via tie molecules (TMs), chains that directly bridge the intercrystalline amorphous layer. TM content will increase with increasing molecular weight (M), or with the fraction of high-M chains in a disperse polymer; it will also increase with decreasing intercrystallite repeat spacing d, which can be manipulated through thermal history and the incorporation of comonomer.  We have examined the failure mode of model narrow-distribution linear PEs and hPNs, where d is varied through both crystallization history (either quenching or slowly cooling) and the incorporation of short branches (at variable levels) that are unable to enter the crystals. For a given (co)polymer composition and thermal history, a rather sharp brittle-to-ductile transition (BDT) is observed with increasing M, at a value MBDT. However, when looking across thermal histories and comonomer contents, MBDT does not correspond to a particular numerical value of the tie molecule fraction (P), calculated by the Huang-Brown approach.  Rather, PBDT increases strongly as crystal thickness decreases, with both PE and hPN showing similar dependences.  We trace this unanticipated dependence to the loss of TMs during drawing, with polymers having thinner initial crystals losing a larger fraction of their TMs. This postulate is confirmed by measurements of the post-draw strain-hardening modulus, which reflects the content of TMs remaining after the material has necked and drawn.  Adding a short amorphous block at the chain end is also found to improve the retention of TMs.  These insights provide guidance for the molecular design of ductile and easily processible polymers (via molecular weight distribution and branch content), and how those desirable characteristics can be preserved through rounds of mechanical recycling.

Speaker Background

Richard A. Register is currently Director of the Princeton Materials Institute and Eugene Higgins Professor in the Department of Chemical and Biological Engineering at Princeton University.  His research interests revolve around micro- and nanostructured polymers, such as semicrystalline polymers, block copolymers, polymer blends, and ionomers, and range across their synthesis, physics, properties, applications, and sustainability.  He served as chair of Princeton’s Department of Chemical and Biological Engineering from 2008-2016, and as Director of the NSF-supported Princeton Center for Complex Materials from 2005-2008.  He received the Charles M.A. Stine Award from the American Institute of Chemical Engineers in 2002, the Princeton’s School of Engineering and Applied Science Distinguished Teacher Award in 2018, its inaugural Distinguished Service Award in 2023, and the inaugural Distinguished Faculty Service Award from Princeton in 2025. He is a Fellow of the American Physical Society, the American Chemical Society, and the American Institute of Chemical Engineers.

Registration deadline: Tuesday, August 18, 1:00 PM.

Registration may close earlier than the nominal deadline if capacity is reached.

This event will be FREE OF CHARGE, but we still require you to fill out the registration form. In particular, we need to have your name and email address for you to be able to participate. Please provide affiliation also if you can, as it helps us judge audience interests.

If you can spare a small amount, GGPF requests an optional donation of $5 (or more) but this is not required to register and attend the webinar.

To register for free, use the pull-down toggle to select "All registrants ($0.00)" choice.

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Webinar Timing: 6:00 PM.

(Zoom meeting room will open earlier)

Attendees who complete the registration form will receive information by email for how to participate. It is requested that people join the meeting invitation well before 6:00 PM to avoid delays.

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For questions or other assistance, contact:

Clayton Henderson

macro2nano@verizon.net

Attendees will be added to the GGPF email announcements list unless they request otherwise.

Introductory Overview:  Polymers in Advanced Semiconductor Technologies

Live virtual short course

October 20-21, 2026

Sponsored by the Golden Gate Polymer Forum.

This course provides an overview of polymer materials commonly implemented in semiconductor technologies, ranging from precision patterning to packaging applications. Presentations will highlight key applications in semiconductor technologies, polymer classes and chemistries, structure-process-property relationships, and relevant characterization techniques and analyses.  Case studies will be employed to highlight the application, utility and nuances of chip and device level considerations, and relevant measurement approaches through real data. The course is designed for all education levels and is accessible even with minimal polymer materials background.

LIST OF TOPICAL AREAS:

- Polymer design considerations for semiconductor technologies: from photolithography through device packaging
- Chemistries and characterization techniques for probing critical application-specific properties
- Rheological experiments to assess processibility and influence of processing on performance
- Topical examples around emerging technologies

INSTRUCTORS:

Tim Long (TL)

Arizona State University
School of Molecular Sciences
Biodesign Institute
School for Engineering of Matter, Transport and Energy
Biodesign Center for Sustainable Macromolecular Materials and Manufacturing
https://longgroup.asu.edu/

Mike Bortner (MB)

Virginia Tech
Department of Chemical Engineering
Macromolecules Innovation Institute
https://www.bortnerlab.com/

Bob Allen (BA)

National Lab of the Rockies (formerly NREL)
Senior Research Fellow
https://research-hub.nlr.gov/en/persons/bob-allen/

Dr. Kyle Arrington (KA)

Intel
Materials Engineering R&D Technologist
https://www.linkedin.com/in/kyle-arrington-628654bb

LECTURE OUTLINE:

1.5 day course, all times Pacific Time

Day 1

8:30  - Introductory Statements from GGPF

8:45  KA1 - More Than Moore: Semiconductor Packaging 101  -  Basics

9:45  break

10:00 BA1 - Moore’s Law: Lithography 101 and Design of Photoresists for Semiconductor Manufacturing

11:00 break

11:15 TL1 - Structure-Property Relationships for Polymeric Networks; Crosslinked Epoxies and Composites  

12:15 Lunch break

1:15 MB1 - Chemorheology: Characterizing Light and Thermal Curing Processing Behavior  

2:15 break

2:30  KA2 - Advanced Packaging Integration – (2.5 D, Die Stacking, Advanced Thermals, and Silicon Photonics)

3:30 break

3:45 BA2 - Photo-Definable Packaging Materials: Strategy, Fundamentals, and Materials

Day 2

8:30 TL2 - Siloxanes for Adhesion Performance: Thermal and Surface Analysis Techniques

9:30 break

9:45 MB2 - Rheology of Particle-Filled Systems

10:45 – break

11:00 – 12:00 all - Future Chemistry Challenges

LOGISTICAL NOTES AND REGISTRATION INFORMATION:

EVENT DATES:

Tuesday October 20 (full day) and Wednesday October 21, 2026 (half day)
Each day's lectures begin 8:30 AM Pacific time
Class materials will be presented using Zoom Webinar. Registrants will receive webinar information shortly before the class begins.

PRICING AND DEADLINES:

Registration deadline dates are tiered, with early, regular, and late registration fees.  All deadline times are Pacific time.

$275 early registration ends Sunday, August 2, 11:59 PM

$375 regular registration ends Monday, October 5, 8:00 PM

$425 late registration, if still available, ends Saturday, October 17, 8:00 PM

No registration is complete until payment is received.
No registrations allowed after 8 PM October 17.
GGPF may close registration earlier if in our opinion class size is becoming too large.

REGISTRATION INFO AND CANCELLATION POLICY:

Register with the form on the GGPF web page:  Register with the form below. Please pay by credit card or PayPal on the GGPF secure registration form. If you absolutely must pay by check, contact GGPF well in advance for information to send checks to our Treasurer.

• No cancellations or refunds are allowed after end of Regular Registration, at 8:00 PM, Oct. 5.  If you cancel before then, you will receive a refund (minus a $50 processing fee).  If you find that you are unable to attend the course after that date, another member of your organization may be substituted for no extra cost.   In the unlikely event that the short course is cancelled by GGPF, you will receive a complete refund (no processing fee).
• If your company requires it, the GGPF Tax ID number will be provided to you by e-mailing a request to Jennifer Hoffman.  Please note that the conference registration fee covers the short course expenses and is not a tax-deductible donation.
• An automated e-mail receipt will be provided as soon as you register and is usually sufficient for corporate reimbursement. If you require a hard copy receipt, please contact Jennifer Hoffman and one can be mailed to you.
• Please register with the email you intend to use for the Zoom event when the class is live. Class Zoom info will be linked to your email account used for registration.  If you need to change the email after registration has already occurred, contact GGPF.
• Course protocols and Zoom information will be provided at minimum one day before the course begins, with reminders afterwards. PLEASE NOTE:  Course-related emails will come from “events@ggpf.ccsend.com”.

CONTACT INFORMATION:

For general questions, including about course content, contact Clayton Henderson, macro2nano@verizon.net.  Please make the subject line of the note include "GGPF Short Course".  Be sure to write if you have not received the course info and Zoom links by the day before, Monday Oct. 19.

For questions about registration, such as payment problems, web page issues, cancellations, substitutions or requests to pay by check, contact Jennifer Hoffman, Jennifer.Hoffman@me.eurofinsus.com

IMPORTANT NOTE ABOUT EMAILS:

Registrants will be added to the GGPF email announcements list.  As a result, you will receive GGPF email announcements from our Constant Contact mail service, showing as coming from events@ggpf.ccsend.com.  Please put this address on your safe list.  On an ongoing basis, GGPF will send out 3 or 4 email announcements per month, and you should see those starting before the short course.  You may unsubscribe at any time from the mail list BUT DO NOT DO THAT BEFORE THE SHORT COURSE IS OVER, or you will miss information about the course that is sent out to registrants, including the Zoom information.