The continuous record of monomer and polymer concentrations, C m and C p , and cumulative weight-average mass, M w , furnished by automatic continuous online monitoring of polymerization reactions (ACOMP) has been harnessed to provide feedback to control reactor monomer flow in order to follow a target trajectory M w,t (t) during linear chain growth free radical polymerization. This was achieved without a detailed kinetic model. Two proportionality parameters to pilot the controller, α and p, result from (i) reaction rate = αC m and (ii) M w,inst = pC m , where M w,inst is instantaneous M w . Using Ansatz values for α and p, the controller periodically recomputes these, based on the ACOMP data stream, in order to follow M w,t (t). A histogram of concentration vs M w,inst estimates the molecular weight distribution width. Invoking an instantaneous distribution provides polydispersities. Results are compared to GPC analysis on end products. The concept of "isomorphic reaction pair" is introduced: two reactions that follow the same trajectory under different reaction variables, e.g., varying T at constant [initiator] and varying [initiator] at T = constant. The controller can be used, as is, for high solids reactions, and extended to copolymerization, including for possible control of composition gradients in controlled radical polymerization.

An automatic molecular weight controller is used in semi‐batch reactions to produce final polymers that contain distinct subpopulations with different molecular weight distributions (MWD). While blending polymers with different MWD is frequently used to make multimodal polymer products, a method is introduced here allowing the multimodal product to be made in successive, automatically controlled stages in the same reactor. The method is demonstrated using free radical polymerization of acrylamide to produce widely separated multimodal MWD. Automatic Continuous Online Monitoring of Polymerization reactions with a Control Interface (ACOMP/CI) was used. Weight average molecular weight (Mw) in the ACOMP/CI was continuously measured with multi‐angle light scattering and ultra‐violet absorption. The controller used two principles: both polymerization rate and instantaneous molecular weight are proportional to monomer concentration. By controlling monomer flow rate into the reactor, the controller produced a targeted amount of polymer with a desired first Mw and then automatically introduced chain transfer agent (CTA) into the reactor to produce a second population of polymers with much lower Mw. Subsequently, reactions were performed to produce trimodal populations. This approach is kindred to multi‐stage synthesis of polymers where distinctly different processes are carried out in succeeding stages to produce polymers with highly specific properties.

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Amphiphilic-grafted nanoparticles (AGNs) composed of silica (SiO 2 ) nanoparticle core and grafted poly(caprolactone)-block-poly[oligo(ethylene glycol) methyl methacrylate] (PCL-b-POEGMA) copolymer were previously reported in the literature with promising oil encapsulation properties. This report serves as an expansion upon that work, where crude oil uptake is thoroughly investigated through ultraviolet light absorption (UV) and differential scanning calorimetry (DSC). The effects of stirring speed and crude oil viscosity are also investigated to determine whether the AGNs follow a diffusion-based mechanism. Polyaromatic hydrocarbon (PAH) encapsulation from UV measurements suggests that these prototype AGNs approximately encapsulate their weight in crude oil and do not have a critical micelle concentration.