ABSTRACT:The radical graft polymerization of vinyl monomers from inorganic ultrafine particles, such as silica, titanium oxide, and ferrite, by use of azo groups introduced onto their surface was investigated. The introduction of azo groups onto the ultrafine particles was achieved by the reaction of glycidyl groups, which were introduced by the reaction of hydroxyl groups on the surface with 3-glycidoxypropyltrimethoxysilane, with 4,4'-azobis(4-cyanopentanoic acid). The amounts of azo groups introduced onto silica, titanium oxide, and ferrite were determined to be 0.07, 0.05, and 0.03 mmol g ·· 1 , respectively. The polymerization of vinyl monomers, such as methyl methacrylate (MMA), styrene, and N-vinylcarbazole (NVC), was found to be initiated by radicals formed by the decomposition of the azo groups. During the polymerization, the polymer was effectively grafted onto these surfaces through propagation from the surfaces; the percentage of grafting of polyMMA onto silica, titanium oxide, and ferrite reached to 45

The grafting of polyesters onto ultrafine inorganic particles, such as silica, titanium oxide, and ferrite, by use of potassium carboxylate (COOK) groups introduced onto the surface was investigated. The introduction of COOK groups onto the surface was achieved by the neutralization of acid anhydride groups, which were introduced by the reaction of 4‐trimethoxysilyltetra‐hydrophthalic anhydride with hydroxy groups on the surface: the amount of COOK groups introduced onto the surface of silica, titanium oxide, and ferrite was estimated to be 1.92, 0.94, and 0.62 mmol/g, respectively. It was found that the anionic ring‐opening copolymerization of epoxides with cyclic acid anhydrides is initiated by COOK groups introduced onto the surface. In the polymerization, polyester formed was effectively grafted onto the surface based on the propagation of the polymer from COOK groups on the surface: the percentage of grafting of polyester from chloromethyloxirane and phthalic anhydride onto silica, titanium oxide, and ferrite reached to 118.3, 82.1, and 7.5%, respectively. The rate of the polymerization and percentage of grafting increased with an increase in COOK group content of the ultrafine particles. The grafting of polyester onto these particles was confirmed by infrared spectroscopy. Polyester‐grafted ultrafine particles produced a stable colloidal dispersion in organic solvent.

ABSTRACT:The introduction of acylium perchlorate groups onto ultrafine silica was achieved by the reaction of silver perchlorate with acyl chloride groups, which were introduced by the treatment of carboxyl groups with thionyl chloride. The introduction of carboxyl groups onto silica surface was achieved by the hydrolysis of acid anhydride groups which introduced by the treatment of silica with 4-trimethoxysilyl tetrahydrophthalic anhydride. Surface acylium perchlorate groups introudced onto silica were capable of initiating cationic polymerization of styrene and polystyrene was effectively grafted onto the surface. The percentage of grafting increased to 65.4%. The grafting efficiency was high during the first few conversion but rapidly decreased with an increase in conversion. This suggests that the grafted polymer propagates from acylium perchlorate groups and that un grafted polymer is gradually formed by a chain transfer of growing polymer cation to the monomer. The cationic ring-opening polymerizations of tetrahydrofuran, styrene oxide, j'i-propiolactone, and e-caprolactone were also initiated by acylium perchlorate groups on silica surface to give the corresponding polymer-grafted silica. The polymer-grafted silica gave a stable colloidal dispersion in good solvents for grafted polymer.

Study designcized, single-blind, controlled trial.ObjectiveTo investigate the efficacy of the Arthrokinematic approach (AKA)-Hakata (H) method for chronic low back pain.Summary of Background DataThe AKA-H method is used to manually treat abnormalities of intra-articular movement.MethodsOne hundred eighty-six patients with chronic nonspecific low back pain randomly received either the AKA-H method (AKA-H group) or the sham technique (S group) monthly for 6 months. Data were collected at baseline and once a month. Outcome measures were pain intensity (visual analogue scale [VAS]) and quality of life (the Roland-Morris Disability Questionnaire [RDQ] and Short Form SF-36 questionnaire [SF-36]).ResultsAt baseline, the VAS, RDQ, and SF-36 scores showed similar levels between the groups. After 6 months, the AKA-H group had more improvement in the VAS (42.8% improvement) and RDQ score (31.1% improvement) than the sham group (VAS: 10.4% improvement; RDQ: 9.8% improvement; both, P < 0.001). The respective scores for the SF-36 subscales (physical functioning, role physical, bodily pain, social functioning, general health perception, role emotional, and mental health) were also significantly more improved in the AKA-H group than in the sham group (all, P < 0.001). The scores for the physical, psychological, and social aspects of the SF-36 subscales showed similar improvement in the AKA-H group.ConclusionThe AKA-H method can be effective in managing chronic low back pain.Trial RegistrationUMIN Clinical Trials Registry (UMIN-CTR) UMIN000006250.