The Arrhenius parameters of the propagation rate coefficient for two linear methacrylates, two branched methacrylates, and two branched acrylates are determined via the pulsed laser polymerization–size exclusion chromatography (PLP-SEC) method. The Mark–Houwink–Kuhn–Sakurada parameters of these polymers are additionally determined via multidetector SEC of narrowly distributed polymer samples obtained through fractionation, allowing for a correct SEC calibration in the PLP-SEC experiment. The data obtained for stearyl methacrylate (SMA, A = 3.45 (−1.17 to +4.46) × 106 L·mol–1·s–1; E a = 21.49 (−1.59 to +1.90) kJ·mol–1) and behenyl methacrylate (BeMA, A = 2.51 (−0.80 to +3.06) × 106 L·mol–1·s–1; E a = 20.52 (−1.43 to +1.85) kJ·mol–1) underpin the trend of increasing k p with increasing ester side chain length. Propylheptyl methacrylate (PHMA, A = 2.83 (−0.82 to 3.15) × 106 L·mol–1·s–1; E a = 21.72 (−1.20 to +1.64) kJ·mol–1) and heptadecanyl methacrylate (C17MA, A = 2.04 (−0.66 to +1.71) × 106 L·mol–1·s–1; E a = 20.72 (−1.42 to +1.38) kJ·mol–1) can be described as a family of branched methacrylates jointly with isodecyl methacrylate and ethylhexyl methacrylate (both published previously), resulting in joint Arrhenius parameters of A = 2.39 (−0.51 to +0.84) × 106 L·mol–1·s–1 and E a = 21.16 (−0.78 to +0.76) kJ·mol–1. In addition, the corresponding branched acrylates are studied applying high-frequency PLP at a 500 Hz laser repetition rate, resulting in Arrhenius parameters of A = 1.05 (−0.42 to +2.81) × 107 L·mol–1·s–1 and E a = 16.41 (−1.99 to +2.42) kJ·mol–1 for propylheptyl acrylate (PHA) and A = 8.15 (−2.83 to +10.3) × 106 L·mol–1·s–1 and E a = 14.66 (−1.49 to +1.66) kJ·mol–1 for heptadecanyl acrylate (C17A).

The Arrhenius parameters of the propagation rate coefficient, k p, are determined via the IUPAC recommended pulsed laser polymerization–size exclusion chromatography (PLP-SEC) method for two linear alkyl acrylates (stearyl and behenyl acrylate), four branched alkyl acrylates (isononyl (INA-A), tridecyl (TDN-A and TDA-A), and henicosyl acrylate (C21A)), and two branched alkyl methacrylates (tridecyl methacrylates (TDN-MA and TDA-MA)) in bulk. Furthermore, the above stated acrylates and heptadecyl acrylate (C17A) were studied in 1 M solution in butyl acetate (BuAc). On the basis of such a wide data basis in combination with the already literature known data of relatives of the herein investigated monomers, we are able to identify and extend global trends and family type behavior for the propagation rate coefficients of a wide array of alkyl (meth)acrylates. In order to ensure a valid SEC evaluation, the polymer specific Mark–Houwnik–Kuhn–Sakurada (MHKS) parameters are determined for each of the polymers, via multidetector SEC analysis (multi angle laser light scattering (MALLS) in combination with differential viscosimetry (Visco) and refractive index (RI)) of narrowly distributed polymer samples obtained via fraction with a preparative SEC column. By employing further physicochemical polymer specific data (e.g., glass transition temperatures (T g)), we provide a hypothesis for the reported trends and family type behaviors: (i) the steady increase of k p with increasing ester side chain length for linear alkyl (meth)acrylates may be explained by a decreasing concentration of the polar ester moieties, resulting in a decreasing stabilization of the attacking radical in the transition state of the propagation reaction, and (ii) the family type behavior of the branched alkyl methacrylates can be understood by considering steric and entropic influences. For the branched alkyl acrylates, no clear trend is detectable, and a family type behavior is clearly not observed in contrast to the corresponding methacrylates.

The Arrhenius parameters of the propagation rate coefficient, kp , are determined employing high-frequency pulsed laser polymerization-size exclusion chromatography (PLP-SEC) for the homologous series of five linear alkyl acrylates (i.e., methyl acrylate (MA), butyl acrylate (BA), dodecyl acrylate (DA), stearyl acrylate (SA), and behenyl acrylate (BeA)) in 1 m solution in butyl acetate (BuAc) as well as in toluene. The comparison of the obtained kp values with the literature known values for bulk demonstrates that no significant solvent influence neither in BuAc nor in toluene on the propagation reaction compared to bulk is detectable. Concomitantly, the kp values in toluene and in BuAc solution display a similar increase with increasing number of C-atoms in the ester side chain as was previously reported for the bulk systems. These findings are in clear contrast to earlier studies, which report a decrease of kp with increasing ester side chain length in toluene. The additional investigation of the longest and shortest ester side chain acrylate (i.e., BeA and MA) over the entire experimentally available concentration range at one temperature (i.e., 50 °C) does not reveal any general concentration dependence and all observed differences in the kp are within the experimental error.

The glass-transition-, melting, and onset decomposition temperatures of a series of tailored polymethacrylates and polyacrylates are systematically investigated. Application fi elds of the investigated polymers include coatings, adhesives, textile, paper, cosmetics, electronics, lubricants, fuel additives, and oil-fi eld or construction chemicals. The present study focuses on linear alkyl, branched alkyl, and amino, as well as ether polymethacrylates and polyacrylates. Novel polymers are introduced with branched C9, C13, C17, and C21 ester, Lupragen, or glycopyranoside ester groups. The thermal characteristics of the novel polymers are analyzed and placed into the context of the thermal data of known polymers fi tting into the homologous series. General trends providing a comprehensive and concise overview of the determined thermal properties are derived. Structureproperty relationships are established and a detailed physicochemical rationale is provided. The study may even allow for a rapid empirical estimation of thermal data of not yet assessed polymer systems.

A well‐known approach toward mechanochromic polymers relies on the incorporation of excimer‐forming fluorophores into a matrix polymer and the disruption of aggregated chromophores when such materials undergo macroscopic mechanical deformation. However, the required aggregates and stress‐transfer processes have so far only been realized with select dye/polymer combinations. As demonstrated here, the utility of this approach can be extended by tethering an excimer‐forming cyano‐substituted oligo(p‐phenylene vinylene) fluorophore to the two ends of a telechelic poly(ethylene‐co‐butylene) and blending small amounts (0.1–2 wt%) of the resulting aggregachromic macromolecule into polymer matrices such as poly(ε‐caprolactone), poly(isoprene), or poly(styrene‐b‐butadiene‐b‐styrene). All blends display mechanofluorochromic responses, and the ratio between the monomer and excimer emission intensities can be used to correlate the luminescence signal to the extent of deformation and to follow subsequent relaxation processes. The developed approach significantly expands the scope of blend‐based mechanoresponsive luminescent materials.

Detailed knowledge of the polymerization mechanisms and kinetics of academically and industrially relevant monomers is mandatory for the precision synthesis of tailor-made polymers. The IUPAC-recommended pulsed-laser polymerization-size exclusion chromatography (PLP-SEC) approach is the method of choice for the determination of propagation rate coefficients and the associated Arrhenius parameters for free radical polymerization processes. With regard to specific monomer classes-such as acrylate-type monomers, which are very important from a materials point of view-high laser frequencies of up to 500 Hz are mandatory to prevent the formation of mid-chain radicals and the occurrence of chain-breaking events by chain transfer, if industrially relevant temperatures are to be reached and wide temperature ranges are to be explored (up to 70 °C). Herein the progress and state-of-the-art of high-frequency PLP-SEC with pulse repetition rates of 500 Hz is reported, with a critical collection of to-date investigated 500 Hz data as well as future perspectives for the field.

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