Supplementary Material

Tuneable Denture Adhesives using Biomimetic

Principles for Enhanced Tissue Adhesion in Moist

Environments

Simrone K Gill,1 Nima Roohpour,2 Paul D Topham,3* Brian J Tighe1

1. Biomaterial Research Unit, School of Engineering and Applied Science, Aston

University, Birmingham B4 7ET, UK.

2. Consumer Healthcare R&D, GlaxoSmithKline, St George’s Avenue, Weybridge,

Surrey, KT13 ODE, UK.

3. Aston Institute of Materials Research, School of Engineering and Applied Science,

Aston University, Birmingham, B4 7ET, UK.

* Corresponding author: p.d.topham@aston.ac.uk

Contents:

Figure S1. GPC traces for P(DMS/S-alt-MAn)1, P(DMS/S-alt-MAn)2 and P(DMS/S-alt-MAn)3.

Figure S2. 1H NMR spectra of P(DMS/S-alt-MAn)1, P(DMS/S-alt-MAn)2, P(DMS/S-alt-MAn)3,

P(DHS/S-alt-MAn)1, P(DHS/S-alt-MAn)2 and P(DHS/S-alt-MAn)3.

Figure S3. FTIR spectra of P(DMS/S-alt-MAn)1, P(DMS/S-alt-MAn)2, P(DMS/S-alt-MAn)3,

P(DHS/S-MAn)1, P(DHS/S-alt-MAn)2 and P(DHS/S-alt-MAn)3.

Figure S4. Representative force-extension curves during the lap shear experiments for (a)

Control (b) P(DMS-S-alt-MA)-containing adhesives and (c) P(DHS-S-alt-MA)-containing

adhesives.

Figure S5. Statistical analysis for verification of normal distribution; (a) histogram (b) normal

Q-Q plot and (c) box plot of data produced for the control in the lap shear technique when

repeated twenty times.

Figure S1. GPC traces for P(DMS/S-alt-MAn)1, P(DMS/S-alt-MAn)2 and P(DMS/S-alt-MAn)3.

Figure S2. 1H NMR spectra of (a) P(DMS/S-alt-MAn)1, (b) P(DMS/S-alt-MAn)2, (c) P(DMS/S-

alt-MAn)3, (d) P(DHS/S-Man)1, (e) P(DHS/S-alt-MAn)2 and (f) P(DHS/S-alt-MAn)3 in d6-

acetone [(CD3)2CO]. N.B. The residual solvent peak for acetone is at 2.0 ppm.

1H NMR spectra were obtained (16 scans) for all isolated polymers synthesized after the

synthesis of P(DMS/S-alt-MAn) and P(DHS/S-alt-MAn) polymers using a Bruker NMR

spectrometer (300 MHz, 7.05 T) and acetone-d6 was used as the solvent.

The 1H NMR spectra for P(DMS/S-alt-MAn) in Figure S2 (a), (b) and (c) show the presence of

methoxy groups at 4.0-3.5 ppm, aromatic groups at 6.5-7.5 ppm (styrenic protons), CH

protons of maleic anhydride at 3.0–3.5 ppm, CH2 and CH styrene backbone protons, at 2-

2.2.5 ppm and 2.5-3.0 ppm, respectively. Following hydrolysis with boron tribromide

changes were seen in (d), (e) and (f) for the CH styrenic protons in the aromatic region (6.2-

7.5 ppm) and the methoxy peaks at 4.0-3.5 ppm disappeared.

Figure S3. FTIR spectra of (a) P(DMS/S-alt-MAn)1, (b) P(DMS/S-alt-MAn)2, (c) P(DMS/S-alt-

MAn)3, (d) P(DHS/S-MAn)1, (e) P(DHS/S-alt-MAn)2 and (f) P(DHS/S-alt-MAn)3. Chemical

structures in (d), (e) and (f) are depicted in their maleic anhydride form for clarity purposes,

however the hydrolysis of the methoxy groups by BBr3 partially hydrolyses the anhydride as

discussed below.

Fourier transform infrared (FTIR) spectra were obtained for the polymers over the range

500-4000 cm-1 for 32 scans.

The FTIR spectra in Figure S3 (a), (b) and (c) show the presence of the following

characteristic peaks for the P(DMS/S-alt-MAn) polymers; C=O anhydride at 1750 cm-1,

Aromatic C=C stretching and C=H bending, C-O arylmethoxy stretching (1250-60 cm -1) and

CH3 (1300 cm-1) rocking bands. Following hydrolysis, the PDHS/S-alt-MAn set of polymers in

(d), (e) and (f) showed the presence of the O-H stretching band at 3200-3600 cm -1 and 1280

cm-1, disappearance of the C-O arylmethoxy stretching (1250-60 cm -1) and CH3 (1300 cm-1)

rocking bands. Reduction in anhydride C=O peak shows that the hydrolysis step carried out

with boron tribromide partially hydrolyses the anhydride, forming a complex between the

carbonyl oxygen atom and the Lewis acid. This is confirmed by the presence of a strong C-O

stretch at 1210 cm-1.

Figure S4. Representative force-extension curves during the lap shear experiments for (a)

Control (b) P(DMS-S-alt-MA) adhesives and (c) P(DHS-S-alt-MA) adhesives.

Figure S5. Statistical analysis for verification of normal distribution; (a) histogram (b) normal

Q-Q plot and (c) box plot of data produced for the control in the lap shear technique when

repeated twenty times.

Figure S5 shows the (a) histogram, (b) normal Q-Q plot and (c) box plot of the data produced

for the control when repeated twenty times in the lap shear adhesion technique used in this

study. The data were also analyzed using Shapiro-Wilk’s and Kolmogorov-Smirnov tests with

values of 0.89 and 0.2, respectively (above 0.05). A skewness value of 0.512 and a kurtosis

of 0.992 were also generated (between -1.96 and +1.96). These values along with the visual

inspection of the data in Figure S5 verify that the data are approximately normally

distributed.