Table 1.

Mechanical properties of PEG-based hydrogels in compression and tension [8,23-25,27-32].

PEG formulation	Concentration [%]	Molecular weight [Da]	Methods	Mechanical property determined	Results
[1] PEG-DM	10	3000	15% unconfined compression at constant rate of 0.2; oscillatory compression of 15%, 1 Hz	Tangent modulus, maximum stress from dynamic compression	0.06 MPa, 0.0084 MPa
	20	3000			0.67 MPa, 0.12 MPa
[23] O-PEG-F (OPF)	75	1000	Constant extension at 10 (lk and 4k) or 25 mm/min (10k) until failure	Tensile modulus, stress and strain at fracture	0.09 MPa, 0.025 MPa, 0.31
	75	4000			0.023 MPa, 0.013 MPa, 0.52
	75	10,000			0.016 MPa, 0.013 MPa, 0.77
[25] PEG-DA and PDMSstar	10	3400	Constant extension at 1 mm/min	Tensile modulus (E)	0.09 MPa
	10	6000			0.07 MPa
[26] PEG-DM	10	3400	Unconfined compression at constant rate of 40 mN/min	Compressive modulus	0.034 MPa
	20	3400			0.36 MPa
	30	3400			0.94 MPa
	40	3400			1.37 MPa
[27] PEG-DA	20	3000	Constant extension at 0.15/min until failure	Quasi-static modulus, ultimate stress and strain	0.4 MPa, 0.2 MPa, 0.37
	65	508			22 MPa, 2.2 MPa, 0.12
	80	508			27 MPa, 1.9 MPa, 0.1
[28] PEG-DM and PEG-LA	10	3000	Unconfined compression at a constant rate of 40–100 mN/min	Compressive modulus	0.06 MPa
	15	3000			0.17 MPa
	20	3000			0.49 MPa
[30] PEG-DA	15	2000	Unconfined compression at constant rate of 0.0005 mm/s until failure	Shear modulus, Young’s modulus, stress and strain at failure	0.01 MPa (G), 0.036 MPa
					(E),0.36 MPa, 0.71
[31] PEG-b-PLA	25	4600	Unconfined compression at constant rate of 400 mN/min	Compressive modulus	0.25 MPa
	50	4600			0.7 MPa
	70	4600			0.9 MPa
[32] PEG-DM	10	4600	Equilibrium unconfined compression at 5–20%; oscillatory compression of 1%, 0.01–10 Hz at 10% offset	Equilibrium compressive modulus and storage modulus	0.05 MPa, 0.04–0.05 MPa
	15	4600			0.19 MPa, 0.15–0.19 MPa
	20	4600			0.27 MPa, 0.25–0.55 MPa

Abbreviations: PEG-diacrylate (PEG-DA), PEG-dimethacrylate (PEG-DM), oligo-(PEG)-fumarate (O-PEG-F), PEG poly (lactic acid) (PEG-b-PLA), PEG-urethane dimethacrylate (PEG-UDM).