Sam Edwards – Continuing the Legacy for Industry-Facing Science’… or … ‘Why don’t you join us for a conversation on the physics of margerine?’ Tom McLeish, Soft Matter Physics and Chemistry, Durham University, UK

Lesson 1: “Industry is Fortune’s Right Hand” Its beginning?...HDPE vs. LDPE melt flow

Lesson 2: “If you would understand anything, observe its beginning and its development”. 1974 1971 1960s

‘But why should they flow at all?’ Star Polymer Puzzles (Kraus, Gruver, Graessley, de Gennes) 1950s!!

Lesson 3: “Read, Mark, Learn” (and browse… the scriptures)

Lesson 4: Love Thy Neighbour(hood chemist).. especially when they can do polyisoprene A. Hakiki and R. N. Young Branched polymers relax from outside in – e.g. H-polymer First, the arms relax by star-like breathing modes Then, the backbone relaxes by “reptation” – but with friction concentrated at the ends of the chain

Lesson 5: ‘If the person you need is in New Jersey – get on the blower J. Rheol., 42, 1, 81-110, (1998).

Lesson 6: Think Big – and think Physics Reaction Chemistry Molecular shape Melt Rheology “Processing”

Linear rheology of arbitrarily branched polymers Relaxation of a branched polymer Suggests an algorithm which monitors amount of polymer relaxation as a function of (logarithmic) time Requires a time-integration along chain-contour variables Chains communicate via “constraint release” Park and Larson 2005 z(t) Das, Read Kelmanson, TCBM, 2006 http://sourceforge.net/projects/bob-rheology

Statistical modelling of molecular architectures (1) Single-site metallocenes, CSTR Cat D UP DOWN Molecules are self-similar and directional! Allows: analytical calculations to calculate MWD, branching distribution, (e.g. D. Read, TCBM, Macromolecules 2001) Monte-Carlo generation of representative set of molecular architectures ( C. Das et al., J. Rheol. 50, 207 (2006).

Industry gives back Can then make predictions for truly polydisperse polymers Set of Dow metallocene polyethylenes (W. De Groot) analysed by Wood-Adams and Dealy Known bu and Mw Two remaining adjustable parameters – matches entire dataset. Das et al., J. Rheol., 50, 207 (2006) Cat D UP DOWN

Statistical modelling of molecular architectures (2) LDPEs, tubular reactors We use “Tobita algorithm” (H. Tobita, J. Polym. Sci. B, 2001) Monte-carlo simulation of free-radical polymerisation;fundamental processes of: initiation chain propagation branch formation scission termination by combination Ri Rp=kp[R][m]

Approximate non-linear rheology: mapping to multimode pom-pom Results Non-linear rheology now predicted with no further fitting!

Approximate non-linear rheology: mapping to multimode pom-pom Tubular LDPE family: analysing how LDPE works Segments relaxing at short, medium and long times

Scattering theoretical neutrons with Sam – and ICI

Lesson 7: Mostly say ‘yes’ to industrial opportunity 20% for critical point

Polyurethanes’ bicontinuous structure: What happens to local strain at percolation? 40% hard phase 50% hard phase

“Strain Amplification”

Strain amplification threshold maps 100 101 102 103

A renormalisation approximation numerics theory

Lesson 8: Work with people cleverer than you Model Parameters from linear theory: A. Likhtman, TCBM (2002) log  [s-1] log G‘, G‘‘ [Pa] REPTATE.com D. Read Ma=25k Mb=57k (deuterated) Synthesis: J. Allgaier, Jülich

Turning neutrons towards Doi-Edwards theory

H-polymer melt relaxation with neutrons =2

Detailed Chain Formulation (GLAMM model) Graham, Likhtman, Milner, TCBM, J. Rheol, 47, 1171-1200 (2003). s R(s) Reptation +CLF flow CR retraction

SANS total flow mapping 13 11 12 8 9 10 5 6 3 4 2 1 T. Gough, J. Bent, R. Richards, N. Clarke, E. de Luca, P. Coates,

A New Service for Industry Launch October 10th 2016