Polymer Journal (2018) 50:967–974 https://doi.org/10.1038/s41428-018-0086-y ORIGINAL ARTICLE Synthesis and thermal investigation of phosphate-functionalized acrylic materials Yun-Fen Peng 1,2,3 ● Ashley Tsai 2 ● Ming-Hsi Huang 1,2 Received: 21 February 2018 / Revised: 23 April 2018 / Accepted: 6 May 2018 / Published online: 6 June 2018 © The Society of Polymer Science, Japan 2018 Abstract Functionalized acrylic materials derived from methyl methacrylate (MMA), 2-hydroxyethyl methacrylate (HEMA), and diethyl 2-(methacryloyloxy)ethyl phosphate (DMP) were synthesized by successive free-radical polymerizations using benzoyl peroxide (BPO) as the initiator and N,N-dimethyl-p-toluidine (DMpT) as the activator. NMR and GPC data showed that successful random copolymerization of MMA and DMP was carried out using the BPO-DMpT system. Moreover, the resulting products were able to react with HEMA monomer, yielding polymers with P(MMA-co-DMP)-b-PHEMA chain structures. Interestingly, the glass transition of DMP/PHEMA-containing copolymers was reduced with respect to the PMMA homopolymer. In addition, the thermal stability was enhanced with increasing DMP content in P(MMA-co-DMP) copolymers and was further enforced by incorporating PHEMA blocks. The presence of DMP/PHEMA segments should improve the thermal behavior of acrylic materials, which is of great interest in the design of versatile bone cements for total joint arthroplasty and functional coatings in targeted drug delivery. Introduction Synthetic polymethacrylates derived from methyl metha- crylate (MMA) and 2-hydroxyethyl methacrylate (HEMA) are considered valuable in the fields of orthopedic surgery and targeted drug delivery [1–3]. PMMA-based bone cement has a pivotal role in fixating implants to bone tissues in total joint arthroplasty [1]. In the pharmaceutical indus- try, PMMA derivatives are commonly used as film-coating agents for both tablet and capsule dosages [2]. Alter- natively, PHEMA has been used in soft contact lenses and artificial cornea; furthermore, it is used as a substrate to prevent cellular adhesion and dispersion [3]. The block copolymerization of MMA and HEMA could be an inter- esting route to modify the intrinsic properties of PMMA and synthesize novel PMMA-based acrylic materials. Block copolymerization could increase the selection of polymers with variable properties available for the design and fabri- cation of cements and/or pharmaceuticals to achieve ver- satile applications. It is well-known that PMMA bone cement materials are biologically inert and do not show activity in bone aug- mentation. However, biomimetic modifications via phos- phorylation have greatly enhanced the heterogeneous nucleation of apatite and cell adhesion behavior [4]. Moreover, PMMA polymer systems bearing different functional groups can potentially be used in broad-spectrum drug release [5, 6]. Previous reports have shown a remarkably high affinity between the amine groups of PMMA derivatives and the phosphate groups of a model drug dexamethasone, which provided the desired release profile of the drug [6]. According to the literature, copolymers of diethyl 2- (methacryloyloxy)ethyl phosphate (DMP) and several alkyl acrylates were synthesized by radical polymerization in benzene using azobis(isobutyronitrile) (AIBN) as an * Ming-Hsi Huang huangminghsi@nhri.org.tw 1 Ph.D. Program in Tissue Engineering and Regenerative Medicine, National Chung Hsing University, 40227 Taichung, Taiwan 2 National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, 35053 Miaoli, Taiwan 3 Department of Oral Hygiene, Hsin Sheng Junior College of Medical Care and Management, 32544 Taoyuan, Taiwan Electronic supplementary material The online version of this article (https://doi.org/10.1038/s41428-018-0086-y) contains supplementary material, which is available to authorized users. 1234567890();,: 1234567890();,: