Preparation and characterization of novel electrospun poly(ε-caprolactone)-based nanofibrous scaffolds

Figures & data

Figure 1. PCL-PEG₄₀₀₀-PCL triblock copolymers.

Figure 2. ¹H-NMR of PCL-PEG₄₀₀₀-PCL triblock copolymers.

Table I. Polymerization of ε-CL with different Mw values of PEG (wt% = 10%), and characterization of copolymers.

Sample	Mw of PEG	PEG (wt. %)	Mw (× 10^− 4)	Mn (× 10^− 4)	Mw/Mn
PCL	–	0	13.5	11.25	1.2
PCL-PEG2000-PCL	2000	10	7.6	5.7	1.33
PCL-PEG3000-PCL	3000	10	8.1	7.29	1.11
PCL-PEG4000-PCL	4000	10	8.4	6	1.4
PCL-PEG6000-PCL	6000	10	9.2	7	1.3

Number average molecular weight (Mn) and Weight average molecular weight (Mw) measured by GPC (calibrated with polystyrene standards).

Table II. The glass transition and melting temperatures of copolymers.

Sample	Tg of copolymer (°C)	Tm of copolymer (°C)
PCL-PEG2000-PCL	− 57.5	33.4
PCL-PEG3000-PCL	− 58.4	31.6
PCL-PEG4000-PCL	− 59.6	30.34
PCL-PEG6000-PCL	− 60.5	29.4

Figure 3. SEM images of the PCL nanofibers; (A) 15KX resolution of PCL, (B) Invert color effected figure for better view of scaffold depth, (C) 7.5KX resolution of PCL, (D) Invert color effected for better view of scaffold depth.

Figure 4. SEM images of (horizontal setup, 10 cm, flow rate of 3 ml/h) electrospun nanofibers, 25 kV, 30% wt polymer, 30 KX: (A); PCL-PEG₂₀₀₀-PCL, (B); PCL-PEG₃₀₀₀-PCL, (C); PCL-PEG₄₀₀₀-PCL, (D);PCL-PEG₆₀₀₀-PCL.