| The main objective of this work is to explore the kinetics of controlled/ "living" free radical photopolymerization process in the present of nitroxide and designed the new bimolecular initiator system to evaluate the probability of nitroxide-mediated "living" free radical photopolymerization of acrylate monomer, such as methyl methacrylate (MMA). Once the kinetics of nitroxide-mediated "living" free radical photopolymerization is thoroughly understood, it will be possible to improve the mediated behavior and controlled mechanism of nitroxide in the living photopolymerization of acrylate monomer and design the novel photosensitive nitroxide-mediated unimolecular photoinitiator. In addition, the series derivatives of reactive hinder amine light stabilizers (r-HALS) were photo-grafted onto the surface of the polyolefm film against photo-oxidative degradation. To fulfill these objectives, the research works and the main conclusions have been performed as follows:1. Five kinds of r-HALS, including APMP (4-acryloyl-l,2,2,6,6-pentamethyl-piperidinyl), MPMP (4-methacryloyl-l,2,2,6,6-pentamethyl-piperidinyl), ATMP (4-acryloyl-2,2,6, 6-tetra-methyl-piperidinyl) and MTMP (4-methacryloyl-2,2,6,6-tetramethyl-piperidinyl), BTMP (4-benzylacryloyloxy-2,2,6,6-tetramethyl-piperidinyl) and TEMPO derivatives, including M-TEMPO (4-methacryloyloxy-2,2,6,6-tetramethyl-piperidinyl-l-oxy) and B-TMEPO(4-ben-zylacryloyloxy-2,2,6,6-tetramethyl-piperidinyl-l-oxy), were synthesized by using the transesterification. And they were characterized by modern analysis techniques, which contain fourier transfer infrared spectroscopy (FTIR), proton nuclear magnetic resonance ('H-NMR), electronic spin resonance (ESR) and differential thermal analysis (DTA).2. The kinetics of nitroxide-mediated controlled/ "living" free radical photopolymerization was dissertated and suggests the difference from the nitroxide-mediated controlled/ "living" free radical thermal polymerization and the disulfides' iniferters process. A HTEMPO/ Darocurll73 bimolecular system was systemically investigated and was employed to synthesize PMMA with living feature.a) The plot of ln[M0]/[M] vs t was shown to be linear at certain exposure periods, and the molecular weight (Mn ) of MMA polymer was observed to changeproportional with conversion Cn %, which indicate a pseudo-living process although its polydispersity (d) changes in the range from 2.1 to 1.6 in the given condition.b) The increment of light intensity is favorable to the living free radical photopolymerization of MMA monomer, the polydispersity of PMMA was decreased from 6 to 1.7. The fact substantially shows the dissociation of the dormant (P-TEMPO) play a key role in the nitroxide-mediated living free radical photopolymerization of acrylates.c) In the photopolymerization of MMA monomer, MMA monomer exhibits anexcellent ability of auto-polymerization, which is a very advantage over thermal polymerization for achieving HTEMPO-mediated living SFR polymerization of MMA monomer. And the side reaction of transfer was great reduced.3. The photo-grafting copolymerization of r-HALS onto the surface of polyolefin film was performed and characterized by the techniques of ATR-FTIR and ESCA spectra. Various conditions of incident light intensity, type of photoinitiator, irradiation time and monomer concentration in the presoaking solution were investigated. The photo-grafting copolymers of LLDPE-g-HALS and BOPP-g-HALS thin films have the better performance against the photo-oxidative degradation. This work presents the successful example of photo-grafting method to make chemical bond linkage of functional groups between surface substrate of polyolefin film and light stabilizers (r-HALS).a) The monomer conversion and the grafting ratio of r-HALS have been obviously effected by various types of photoinitiator, including BP, Darocur1173, Irgacurel84 and Irgacure65 1 . BP shows the most effective photoinitiator for photo-grafting copolymerization.b) We have developed new method that...
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