Research Article Synthesis, Characterization, and Visible Light Curing Capacity of Polycaprolactone Acrylate Jy-Jiunn Tzeng, 1 Yi-Ting Hsiao, 1 Yun-Ching Wu, 1 Hsuan Chen, 1 Shyh-Yuan Lee, 1,2,3 and Yuan-Min Lin 1,2 1 Department of Dentistry, National Yang-Ming University, No. 155, Sec. 2, Linong St., Beitou District, Taipei 112, Taiwan 2 Department of Stomatology, Taipei Veterans General Hospital, No. 201, Section 2, Shipai Road, Beitou District, Taipei City 112, Taiwan 3 Department of Dentistry, Taipei City Hospital, No. 145, Zhengzhou Rd., Datong District, Taipei 103, Taiwan Correspondence should be addressed to Yuan-Min Lin; ymlin@ym.edu.tw Received 24 October 2017; Revised 13 February 2018; Accepted 27 March 2018; Published 8 May 2018 Academic Editor: Weijie Fu Copyright © 2018 Jy-Jiunn Tzeng et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Polycaprolactone (PCL) is drawing increasing attention in the feld of medical 3D printing and tissue engineering because of its biodegradability. Tis study developed polycaprolactone prepolymers that can be cured using visible light. Tree PCL acrylates were synthesized: polycaprolactone-530 diacrylate (PCL530DA), glycerol-3 caprolactone triacrylate (Glycerol-3CL-TA), and glycerol-6 caprolactone triacrylate (Glycerol-6CL-TA). PCL530DA has two acrylates, whereas Glycerol-3CL-TA and Glycerol-6CL-TA have three acrylates. Te Fourier transform infrared and nuclear magnetic resonance spectra suggested successful synthesis of all PCL acrylates. All are liquid at room temperature and can be photopolymerized into a transparent solid afer exposure to 470nm blue LED light using 1% camphorquinone as photoinitiator and 2% dimethylaminoethyl methacrylate as coinitiator. Te degree of conversion for all PCL acrylates can reach more than 80% afer 1 min of curing. Te compressive modulus of PCL530DA, Glycerol- 3CL-TA, and Glycerol-6CL-TA is 65.7±12.7, 80.9±6.1, and 32.1±4.1 MPa, respectively, and their compressive strength is 5.3±0.29, 8.3 ± 0.18, and 3.0 ± 0.53 MPa, respectively. Tus, all PCL acrylates synthesized in this study can be photopolymerized and because of their solid structure and low viscosity, they are applicable to sof tissue engineering and medical 3D printing. 1. Introduction Biodegradable materials are drawing increasing attention in the feld of 3D printing because they can be used to print body implants, tissue engineering scafolds, and even drug- releasing capsule [1–3]. So far, polylactic acid (PLA) is one of the most common biodegradable materials used in 3D printing [4–6]. PLA can be easily heated above its melting temperature of 150 ∘ C–160 ∘ C and squeezed out from a nozzle in a 3D printer based on fused deposition modeling (FDM) [7, 8]. Te major problem of FDM 3D printers is that they have low resolution compared with using stereolithography (SLA) or digital light processing (DLP) 3D printers [9, 10]. Another problem of FDM 3D printers is the slow printing speed because it forms a 3D object by stacking many thin material lines, consequently taking several hours to print a small object [11, 12]. Tis study developed biodegradable materials for use in DLP 3D printers in the near future. Te biodegradability of common polymers, such as polyglycolide (PGA), PLA, and polycaprolactone (PCL) polyesters, depends on their structures [13–15]. Teir ester bonds undergo hydrolysis on reaction with water. Polyesters with longer alkyl backbone and more alkyl side chains are less hydrophilic and therefore have a longer degradation rate [16]. In general, PCL has a longer degradation rate than does PLA, and PLA shows a longer degradation rate than does PGA. Because of its longer degradation time, PCL has several potential tissue engineering and medical 3D printing applications. PCL is a popular biodegradable material for resin addi- tives, small scale modeling, and bone tissue engineering [17– 22]. It can be synthesized by the ring-opening polymerization of -caprolactone [23, 24]. It has been prepared as scafolds by using salt-leaching and thermally induced phase separation techniques. However, these two methods are inconsistent and therefore are unsuitable for largescale production. Hindawi BioMed Research International Volume 2018, Article ID 8719624, 8 pages https://doi.org/10.1155/2018/8719624