| Cyclotriphosphazene is a kind of heterocyclic compound which is composed of phosphor us-nitrogen single and double bonds alternatively and its six-member ring structure,is similar to the type of plane structure of aromatic ring. Because of its good molecular design, phosph orus atoms can be linked with the same or different side groups to form various cyclotriphosp hazene derivative by replace chemical reaction and so on; As its structure is rich in phosphoru s and nitrogen atoms, cyclotriphosphazene derivative has excellent heat resistance and flame r etardant and can be applied in biology, medicine, pesticides, environmental protection, materi als, and other areas.In this work, hexachlorocyclotriphosphazene is used as a matrix for the synthesis of two new types of cyclotriphosphazene derivatives. The first category is a kind of cyclotriphosphazene derivatives with symmetry. Three phosphorus atoms are linked with the same group, and radical polymerization can be carried out. To adjust the density of active groups, the second category, asymmetric cyclotriphosphazene derivatives, is synthesized by connecting different groups.First, p-hydroxy-benzoic acid allyl ester and p-hydroxyphenyl maleimide was synthesized, and a six-chloro cyclotriphosphazene was as the basic raw material to synthesize structure symmetry cyclotriphosphazene six group substituted benzoic acid allyl ester(HABP) and six cyclotriphosphazene group substituted phenylmaleimide(HCPMI) by nucleophilic substitution and other multi-step reaction. Hydroxybenzoic acid allyl ester with C = C and p-hydroxyphenyl maleimide were introduced onto the ring cyclotriphosphazene respectively. Second, 2,2 'biphenol was as the groups modifier of hexachloro cyclotriphosphazene. Two closed P-Cl bond(single seal segment) of t1 and four closed P-Cl bond(two ends) of t2 were prepared,, and then reacted with p-hydroxy-benzoic acid allyl ester(a series) and 2-allyl phenol(b series) respectively. Then four asymmetric cyclotriphosphazene compound a1t1, b1t1, a1t2 and b1t2 were synthesized. The synthesized cyclotriphosphazene compounds were characterized by means of melting point measurement, IR, 1H NMR and 31 P NMR. The single crystal structure of a group six cyclotriphosphazene substituted benzoic acid allyl ester, t1, a1t1 were cultivated, and then the diffraction analysis of a single crystal structure was thefurther evidence of the obtained compound being the target compound and being with steady spatial conformation.This article was also prepared as BPO was initiator, a1t1 with C = C and methyl methacrylate(MMA) were to a certain percentage of free radical copolymerization. It was found that: when the polymerization activity of a1t1 was lower and the content of a1t1 was higher than 1/4 in copolymer component, viscous oligomer could only be got. By GPC of 1: 4 cyclotriphosphazene / methyl methacrylate had a molecular weight of the test, which reached Mw 237436, Mn of 36509, Mw / Mn of 6.503.Properties of the copolymers were analyzed by thermal gravimetric analysisand differential scanning calorimetry thermal and the flame retardant properties of the copolymer resin was test by the limiting oxygen index and vertical burn detection. The results showed that the introduction of three cyclic phosphazene can improve the thermal decomposition temperature of PMMA, the best ratio of copolymer resin was a1t1: MMA = 1: 4, and at the same time, d5% of the resin of 234 ?, d10% to 277 ?, char yield 8.37% at 800 ?under an argon atmosphere. When the temperature was higher than 450 ?, PMMA was completely decomposed, and HPMMA was 8.37% of carbon yield. The flame retardant of cyclotriphosphazene derivative HPMMA and the PMMA were characterized by limiintg oxygen index(LOI) and vertical flame test methods.The flame retardant of PMMA increased as cyclotriphosphazene compound content increased, the LOI of pure PMMA was 17.50; a1t1: MMA = 1: 4, LOI is 20.85, UL-94 is V-1. |
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