Benzyl methacrylate

2-Hydroxyethyl methacrylate (HEMA) and benzyl methacrylate (BzMA) were purchased from Sigma Aldrich and passed through a basic alumina column prior to use in order to remove the inhibitor. 2,2′-Azobisisobutyronitrile (AIBN) was purchased from Molekula and was recrystallised from methanol prior to use. 4-Cyano-4-(phenylcarbonothioylthio) pentanoic acid (CPTP) RAFT agent was purchased from Sigma Aldrich and used as received. Reagent grade methanol and diethyl ether were purchased from Fisher Scientific. Dimethyl sulfoxide-d₆ and methanol-d₄ for ¹H NMR analysis were purchased from Goss Scientific. 1-Ethyl-3-methylimidazolium dicyanamide [EMIM][DCA] was acquired from BASF.

(2-(Methacryloyloxy)ethyl)trimethylammonium chloride (MOTMA-Cl, 80 wt% solution in water), stearyl methacrylate (SMA), and benzyl methacrylate (BzMA, 96%) monomers were all purchased from Sigma-Aldrich (UK). BzMA monomer was passed through a basic alumina column to remove inhibitor prior to use. Sodium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate (Na-TFPhB) was a gift from Merck Chemicals Ltd (UK). 2,2-Azobisisobutyronitrile (AIBN) initiator was purchased from Molekula (UK), and tert-butyl peroxy-2-ethylhexanoate (T21s) initiator was a gift from AkzoNobel (The Netherlands). Cumyl dithiobenzoate (CDB, 99%) was purchased from Sigma-Aldrich (UK) and used a supplied. Solvents for synthesis and purification (dichloromethane, toluene, tetrahydrofuran, ethanol, methanol, and isopropanol) were purchased from either VWR, Sigma-Aldrich, or Fisher (UK) and were used as supplied. Deuterated solvents were obtained from either Cambridge Isotope Laboratories (USA) (acetone-d₆ and dichloromethane-d₂) or Sigma-Aldrich (UK) (chloroform-d₃). Solvents to prepare dispersions were obtained from either Sigma-Aldrich (UK) (n-dodecane, ≥99%) or Alfa Aesar (UK) (n-hexadecane, 99%).

glycerol monomethacrylate (GMA, purity 97%) was obtained from GEO speciality chemicals (Hythe, UK) and was used as received. 2,2,2-Trifluoroethylmethacrylate (TFEMA, 99%), lauryl methacrylate (LMA, 96%), n-dodecane (>99%), glycerol (>99%), sucrose (>99.5%), Nile red, CD₃OD, tetrahydrofuran (THF), dimethylformamide (DMF) (CD₃)₂CO, lithium bromide (LiBr), CDCl₃, dimethyl sulfoxide (DMSO), triethylamine, 3,5-di-tert-4-butylhydroxytoluene (BHT), toluene, benzyl methacrylate (BzMA, 96%), 4,4′-azobis(4-cyanovaleric acid) (ACVA, >97%), benzophenone (>99%), pyrene (>99%), 2-cyanopropyldithiobenzoate (CPDB, >97%), 2-phenylethanethiol, sodium hydride (60% in mineral oil), diethyl ether, carbon disulfide, iodine, sodium thiosulfate, sodium sulfate, ethyl acetate and n-hexane were purchased from Sigma Aldrich (UK). tert-Butyl peroxy-2-ethylhexanoate (Trigonox 21S or T21s) initiator was supplied by AkzoNobel (The Netherlands) and sodium dodecylsulfate (SDS) was obtained from BDH laboratory supplies (Poole, UK). benzyl methacrylate was passed through basic alumina prior to use; all remaining reagents were used as received unless otherwise stated. Deionized water (pH 6.1 at 20 °C) was used for all experiments described herein. All solvents used were of HPLC grade.

The monomer benzyl methacrylate (BzMA), the crosslinker bisphenol A ethoxylate diacrylate (Mn~512, BPA), and the photoinitiator 2,2-dimethoxy-2- phenylacetophenone (DMPA) were purchased from Sigma Aldrich and used as received without further purification. This monomer and difunctional crosslinker combination, which is similar to that reported by Safranski and Gall [24 ], was selected because it enables the synthesis of a series of SMPs with tailorable crosslink densities and glass transitions above body temperature in the range of 65 to 75°C. benzyl methacrylate was also selected because Safranski and Gall [24 ] demonstrated that poly(benzyl methacrylate) thermoset SMPs have higher toughness than numerous other thermoset acrylics. Four thermoset acrylic BzMA-BPA copolymers containing 5, 15, 25, and 35 mole% BPA and 0.5 weight% DMPA were prepared in 51 × 76 × 0.4 mm sheets by bulk UV curing. After massing, the monomer, crosslinker, and photoinitiator mixtures were injected between 51 × 76 mm glass slides coated with Rain-X separated by 0.4 mm spacers and cured for 99 minutes using 365nm UV irradiation inside a UVP CL-1000 crosslinking chamber. The cured thermoset films were then postcured at 130°C with vacuum at 1 torr for 12 hours and subsequently stored under desiccation.

Benzyl methacrylate (BzMA, 96%), S-(2-cyanoprop-2-yl)-S-dodecyltrithiocarbonate (CTA, 97%), styrene (99%) and Nile red (98%) were purchased from Sigma-Aldrich. Tetrahydrofuran (THF, 99+%), toluene (CP), anisole (AR), hexane (AR) were purchased from Sinopharm Chemical Reagent. 2,2′-Azobis(2-methylpropionitrile) (AIBN, 99%) was purchased from Aladdin Reagent. N, N′-Bis(acryloyl)cystamine (BAC, 98%) was purchased from Alfa-Aesar. All liquid monomers were passed through a column of Al₂O₃ to remove the inhibitor prior to use.