Stephen L Craig

Journal article Macromolecular rapid communications · January 2021 Featured Publication The molecular processes that accompany dynamic mechanical response to large deformations at high strain rate (≈1000 s-1 or higher) underlie the early stages of damage in materials, but understanding of material response in this regime is typical ... Full text Cite

Enhanced polymer mechanical degradation through mechanochemically unveiled lactonization.

Journal article Nature communications · October 2020 Featured Publication The mechanical degradation of polymers is typically limited to a single chain scission per triggering chain stretching event, and the loss of stress transfer that results from the scission limits the extent of degradation that can be achieved. Here, we rep ... Full text Cite

Oxidative regulation of the mechanical strength of a C-S bond.

Journal article Chemical science · September 2020 Featured Publication The mechanical strength of individual polymer chains is believed to underlie a number of performance metrics in bulk materials, including adhesion and fracture toughness. Methods by which the intrinsic molecular strength of the constituents of a given poly ... Full text Cite

Mechanochemical strengthening of a synthetic polymer in response to typically destructive shear forces.

Journal article Nature chemistry · September 2013 Featured Publication High shear stresses are known to trigger destructive bond-scission reactions in polymers. Recent work has shown that the same shear forces can be used to accelerate non-destructive reactions in mechanophores along polymer backbones, and it is demonstrated ... Full text Cite

A backbone lever-arm effect enhances polymer mechanochemistry.

Journal article Nature chemistry · February 2013 Featured Publication Mechanical forces along a polymer backbone can be used to bring about remarkable reactivity in embedded mechanically active functional groups, but little attention has been paid to how a given polymer backbone delivers that force to the reactant. Here, sin ... Full text Cite

From molecular mechanochemistry to stress-responsive materials

Journal article Journal of Materials Chemistry · February 14, 2011 Featured Publication Current activity in, and future prospects for, the incorporation of mechanochemically active functional groups ("mechanophores") into polymers is reviewed. This area of research is treated in the context of two categories. The first category is the develop ... Full text Cite

Molecular stress relief through a force-induced irreversible extension in polymer contour length.

Journal article Journal of the American Chemical Society · November 2010 Featured Publication Single-molecule force spectroscopy is used to observe the irreversible extension of a gem-dibromocyclopropane (gDBC)-functionalized polybutadiene under tension, a process akin to polymer necking at a single-molecule level. The extension of close to 28% in ... Full text Cite

Trapping a diradical transition state by mechanochemical polymer extension.

Journal article Science (New York, N.Y.) · August 2010 Featured Publication Transition state structures are central to the rates and outcomes of chemical reactions, but their fleeting existence often leaves their properties to be inferred rather than observed. By treating polybutadiene with a difluorocarbene source, we embedded ge ... Full text Cite

1,2,3-Triazole CH...Cl(-) contacts guide anion binding and concomitant folding in 1,4-diaryl triazole oligomers.

Journal article Angewandte Chemie (International ed. in English) · January 2008 Featured Publication Full text Cite

Physical organic chemistry of supramolecular polymers.

Journal article Langmuir : the ACS journal of surfaces and colloids · February 2007 Featured Publication Unlike the case of traditional covalent polymers, the entanglements that determine properties of supramolecular polymers are defined by very specific, intermolecular interactions. Recent work using modular molecular platforms to probe the mechanisms underl ... Full text Cite

Single-molecule force spectroscopy of bimolecular reactions: system homology in the mechanical activation of ligand substitution reactions.

Journal article Journal of the American Chemical Society · March 2006 Featured Publication The mechanochemistry of the bimolecular nucleophilic substitution of DMSO for substituted pyridines at a square-planar pincer Pd(II) center was investigated using single-molecule force spectroscopy (SMFS). The SMFS data are interpreted in terms of the Bell ... Full text Cite

Small-molecule dynamics and mechanisms underlying the macroscopic mechanical properties of coordinatively cross-linked polymer networks.

Journal article Journal of the American Chemical Society · October 2005 Featured Publication Specific metal-ligand coordination between bis-Pd(II) and Pt(II) organometallic cross-linkers and poly(4-vinylpyridine) in DMSO defines a three-dimensional associative polymer network. Frequency-dependent dynamic mechanical moduli of a series of four diffe ... Full text Cite

Orthogonal control of dissociation dynamics relative to thermodynamics in a main-chain reversible polymer.

Journal article Journal of the American Chemical Society · December 2003 Featured Publication A pair of homologous and soluble reversible polymers display nearly identical solution structures but dramatically different dissociation dynamics (1.0 vs ca. 100 s-1) along their main chains. The polymers are formed by organopalladium-pyridine coordinatio ... Full text Cite