Toward Self-Healing Hydrogels Using One-Pot. Thiol Ene Click and Borax-Diol Chemistry

Size: px

Start display at page:

Download "Toward Self-Healing Hydrogels Using One-Pot. Thiol Ene Click and Borax-Diol Chemistry"

Roderick Caldwell
5 years ago
Views:

1 Toward Slf-Haling Hydrogls Using On-Pot Thiol En Click and Borax-Diol Chmistry Lirong H 1, Danil Szopinski 1, Yang Wu 1, Grrit A. Luinstra 1, Patrick Thato* 1 1 Institut for Tchnical and Macromolcular Chmistry, Univrsity of Hamburg Bundsstrass 45, D Hamburg, Grmany Exprimntal part Matrials and instrumnts: Poly(thyln glycol) M n = 700 g/mol, dithiothritol (DTT), borax wr purchasd from Sigma-Aldrich. Phosphat buffr salin (ph 7.4, 1x stock solution) was frshly prpard bfor using. Ultra-pur watr (with a rsistanc highr than 18.2 MΩ) was obtaind from Smart2Pur TM (thrmo scintific, USA). 1 H NMR spctra wr carrid out with a Brukr 300 MHz FT-NMR spctromtr in D 2 O. 11 B NMR spctra wr rcordd on a Varian Gmini-2000 spctromtr in D 2 O. Molcular wights wr masurd on a Gl Prmation Chromatography (P580 pump from Dionx, USA) quippd with Shodx RI-71 rfraction dtctor M ammonium hydrogn carbonat in a mixtur of actonitril and watr (20:80 in volum) was usd as th lunt solvnt. Th molcular wight and distribution was calculatd basd on Polyhydroxymthacrylat. Rhological masurmnts wr prformd on a AR-G2 controlld strss rhomtr (TA Instrumnts, Nw Castl, USA) with a plat-plat gomtry 1

2 (diamtr = 25 mm). Hydrogl morphology was masurd with Scanning Elctron Microscopy (SEM) quippd with a LEO 1525 FE-REM microscop. Prparation of thiol-micahl polyaddition PEG-basd hydrogl. A 1:1 molar ratio of ngroup and thiol-group was usd for all glations by thiol-n Michal polyaddition chmistry. For xampl, a hydrogl with 12.5 wt% polymrs and 0.05 mol/l was prpard according to th following procdur: PEGDA (100 mg, 0.14 mm) and DTT (22 mg, 0.14 mm) wr dissolvd in 0.5 ml watr, 0.5 ml of 0.1 mol/l borax solution was addd to th mixtur undr vigorous stirring for 10 s. Th solution was allowd to stay at 25 C for a whil and th glation tim was chckd by tub invrsion mthod. Hydrogls with diffrnt polymr concntration and borax contnt wr prpard according th sam mthod. Sampl prparation for rhology tsts. Aftr mixing PEGDA (2g, 2.8 mm) and DTT (440 mg, 14 mm) in 2.5 ml watr, 2.5 ml PBS solution was addd to th solution. Th mixtur was allowd to stir for 30 minuts at 25 C. Th solution was lyophilizd for 24 h to yild sticky polymrs. A small amount of polymr was takn to prfrom FT-IR masurmnts to confirm th convrsion of th thiol-n Michal polymrization. Th yildd polymr was dividd to svral vials with idntical amount of polymrs. Th sampls containing idntical amount of polymr (12.5 wt%) with varid borax concntration ranging from 0.07 to 0.50 (n borax : n DTT ) wr prpard. Hydrogls wr kpt at 25 C for 20 minuts bfor conducting rhology tsts. Rhology tsts. Rhological masurmnts wr prformd on a AR-G2 controlld strss rhomtr (TA Instrumnts, Nw Castl, USA) with a plat-plat gomtry (diamtr = 25 mm). SAOS xprimnts wr carrid out at a frquncy rang of 0.1 to 100 rad s -1, starting from th highst frquncy. Th strain was kpt within th limits of th linar viscolastic rgim at a 2

3 tmpratur of 25 C. Th rubbr-lastic platau was dtrmind from th frquncy indpndnt rgim of th storag modulus. Th ntwork paramtrs (molcular wight btwn nt points * M υ, crosslink dnsity and crosslink distanc ξ ) wr calculatd according to quation M * crt = G ' p (1) G' p N υ = RT A (2) ( ) 1 3 ξ = ν (3) whr c is th polymr concntration, R th univrsal gas constant, N A th Avogadro constant and T th tmpratur. Hydrogl slf-haling. Two idntical disk of hydrogls wr prpard by mixing PEGDA (100 mg, 0.14 mm), DTT (22 mg, 0.14 mm) in 0.5 ml watr and 0.5 ml of 0.1 mol/l borax. For bttr visualization, on of th hydrogl was colord by mixing in a fluorscnc dy. Both gls wr cut into idntical pics. Two pics, on with and on without colour, wr put togthr in contact to allow slf-haling. SEM charactrization. A sampl of hydrogl was fr-drid undr rducd prssur and was attachd on a SEM pin mount and coatd with carbon prior to masurmnt. 3

Tabl S1 Glation tims of PEGDA and DTT undr diffrnt concntrations of borax and polymr prcursors Entry # Polymr concntration (wt%) C borax (mmol/ml) Glation tim 1 6.25 0.05 No glation 2 12.5 0.01 20 3 12.

4 Tabl S1 Glation tims of PEGDA and DTT undr diffrnt concntrations of borax and polymr prcursors Entry # Polymr concntration (wt%) C borax (mmol/ml) Glation tim No glation Figur S1 SEM imags of PEGDA700+DTT hydrogl catalyzd by 0.07 M borax. Sampl was prpard by lyophilization. 4

Figur S2 From right to lft: linar polymr (12.5 %) obtaind from thiol-n polymrization of PEGDA and DTT catalyzd by PBS (P 0 ); linar polymr (12.5%) with 0.01 mol/l, 0.05 mol/l and 0.

5 Figur S2 From right to lft: linar polymr (12.5 %) obtaind from thiol-n polymrization of PEGDA and DTT catalyzd by PBS (P 0 ); linar polymr (12.5%) with 0.01 mol/l, 0.05 mol/l and 0.07 mol/l borax, rspctivly. Tabl S2. Ntwork paramtrs (molcular wight btwn ntpoints, crosslink dnsity and crosslink distanc) for polymr solutions (c = 12.5 wt%, M n = 7720 g mol -1 ) with various borax/dtt molar ratios. N(borax)/n(DTT) G p [Pa] * M [g mol -1 ] υ [m -3 ] ξ [nm]

1). Figur S4. Hydrogl formd from PEGDA (0.14 mm/ml) and DTT (0.14 mm/ml) with borax (0.

6 Figur S3. Th gl rlaxation tim t as a function of th Borax/DTT molar ratio. Th dashd lin is th rsult of a last-squars fit, following a linar rlationship (slop = 1). Figur S4. Hydrogl formd from PEGDA (0.14 mm/ml) and DTT (0.14 mm/ml) with borax (0.05 mm/ml) at ph 9. Solution producd aftr th hydrogl was acidifid to ph=3. This procss is rvrsibl. 6

80 o C 18 o C Figur S5 Hydrogl formd from PEGDA (0.14 mm/ml) and DTT (0.

Hydrogl rformd aftr cooling th solution at 18 o C. Rfrncs (1) Hinrich, G.

In Polymr Physics SE - 2; Advancs in Polymr Scinc; Springr Brlin

7 80 o C 18 o C Figur S5 Hydrogl formd from PEGDA (0.14 mm/ml) and DTT (0.14 mm/ml) at ph 9. Solution was producd aftr hating to 80 o C. Hydrogl rformd aftr cooling th solution at 18 o C. Rfrncs (1) Hinrich, G.; Straub, E.; Hlmis, G. In Polymr Physics SE - 2; Advancs in Polymr Scinc; Springr Brlin Hidlbrg, 1988; Vol. 85, pp (2) Sidl, C.; Kulick, W.; Hß, C.; Hartmann, B.; Lchnr, M. D.; Lazik, W. Starch- Stärk 2004, 56,

Phosphonate-Functionalized Polystyrene Microspheres with Controlled Zeta Potential for Efficient Uranium Sorption

Phosphonate-Functionalized Polystyrene Microspheres with Controlled Zeta Potential for Efficient Uranium Sorption Elctronic Supplmntary Matrial (ESI) for RSC Advancs. This journal is Th Royal Socity of Chmistry 2016 Supporting Information Phosphonat-Functionalizd Polystyrn Microsphrs with Controlld Zta Potntial for