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A polymeric one-component type II photoinitiator (PDABPP) based on 4,4'-dihydroxybenzophenone (DHBP), acryloyl chloride, and piperazine was synthesized, and its structure was confirmed by GPC and [.sup.1.H] NMR. The photopolymerization kinetics of the photoinitiator was studied by real-time infrared spectroscopy. It indicated that PDABPP was a more effective photoinitiator than that of benzophenone (BP)/triethylamine (TEA). The rate of polymerization and final conversion increased, and the induction period shortened with increase of PDABPP concentration, light intensity, and amine concentration. The kinetics of photopolymerization for tripropylene glycol diacrylate (TPGDA) incorporating PDABPP in the presence of different tertiary amines as the initiating system indicated that the PDABPP/TEA combination exhibited the highest polymerization rates among the PDABPP/amines combinations. POLYM. ENG. SCI., 48:884-888, 2008. © 2008 Society of Plastics Engineers, INTRODUCTION Photopolymerization science and technology has been obtaining much attention in recent years because of its various industrial applications in coatings, adhesives, printing inks, photoresists, and biomaterials [1-4]. A typical [...]

A one-component type II photoinitiator (PDBP), based on 4-hydroxybenzophenone (HBP), acryloyl chloride, and piperazine, was synthesized and its structure was confirmed by 1H-NMR. The photopolymerization kinetics of the photoinitiator was studied by real-time Infrared spectroscopy (FT-IR). It indicated that PDBP was a more effective photoinitiator than that of BP/triethylamine (TEA). The rate of polymerization, final conversion increased and the induction period shortened with increase in PDBP concentration, light intensity, and amine concentration. The kinetics of photopolymerization for TPGDA incorporating PDBP in the presence of different tertiary amines as the initiating system indicated that the PDBP/TEA combination exhibited the highest polymerization rates among the PDBP/amine combinations. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: To explore the effectiveness of interlocking intramedullary nail fixation system for Sanders type Ⅱ and Ⅲ calcaneal fractures by comparing with open surgery., Methods: Forty patients (40 feet) with Sanders type Ⅱ and Ⅲ calcaneal fractures, who were admitted between May 2020 and December 2022 and met the selection criteria, were included in the study. They were randomly allocated into control group and minimally invasive group using a random number table method, with 20 cases in each group. The patients were treated with the interlocking intramedullary nail fixation system in the minimally invasive group and with steel plate internal fixation via a lateral L-shaped incision in the control group. There was no significant difference between the two groups ( P >0.05) in terms of gender, age, fracture classification and side, cause of injury, time from injury to admission, and preoperative width, length, height, Böhler angle, and Gissane angle of the calcaneus. The operation time, intraoperative blood loss, incision length, hospital stay, fracture healing time, incidence of complications, as well as pre- and post-operative imaging indicators (Böhler angle, Gissane angle, width, height, and length of the calcaneus) and American Orthopaedic Foot and Ankle Society (AOFAS) score of foot were recorded and compared between the two groups., Results: The incision length, operation time, and hospital stay of the minimally invasive group were significantly shorter than those of the control group, and the intraoperative blood loss significantly reduced ( P <0.05). All patients of the two groups were followed up, with the follow-up time of 8-12 months (mean, 10.2 months) in the minimally invasive group and 8-12 months (mean, 10.4 months) in the control group. No complication occurred in the minimally invasive group after operation. One case of incision epidermal necrosis and 1 case of traumatic arthritis occurred in the control group after operation. However, there was no significant difference in the incidence of complications between the two groups ( P >0.05). At last follow-up, the AOFAS score was significantly higher in the minimally invasive group than in the control group ( P <0.05). Imaging examination showed that the calcaneal fractures of the two groups healed, and there was no significant difference in healing time between the two groups ( P >0.05). Compared with preoperative conditions, the Böhler angle and Gissane angle of the calcaneus in the two groups significantly increased, the width narrowed, and the height and length increased at 3 days after operation and the last follow-up, with significant differences ( P <0.05). There was no significant difference between 3 days after operation and last follow-up ( P >0.05). There was no significant difference between the two groups at each time point ( P >0.05)., Conclusion: The interlocking intramedullary nail fixation system in treatment of Sanders type Ⅱ and Ⅲ calcaneal fractures has the advantages of minimal trauma, shortened hospital stay, reliable fracture reduction and fixation, and satisfactory foot function recovery.