| Theβ-modification of proplylene copolymers, namely, PP-B and PP-R, was studied in this paper. Eight adipates and pimelates which were designed and synthesized in the lab, as well as commercial product TMB-5 were used asβ-nucleaters to modify PP-B and PP-R.Among all the pimelates, PA-Ca, PA-Ba and PA-Mg are all found to make great influence on the beta-modificaion of PP-B, and the order in efficiency of beta nucleation is arranged as PA-Ca>PA-Ba>PA-Mg, PA-Na is the weakest nucleater of PP-B. When the amount of PA-Ca is 0.1%, the beta and total melting enthalpyand, respectively, reach to the maximum value of 38.1J and 97.2J, in addition, the notch impact strength has raised 67% form 6.84 to 11.40 kJ·m-2.Among all the adipates which could work as beta-nucleaters of PP-B, both of AA-Na and AA-Ba are found to make great impact on PP-B, on the contrary, little contribultion was found when AA-Ca was employed. Both of AA-Na and AA-Ba can raise the general crystallinity of PP-B a lot, and the KDSC values increase to 67.3 and 69.1, respectively. When the amount of AA-Na is 0.2%, the notch strength of PP-B reaches to the maximum value which has raised 23% from 6.84 to 8.42 kJ·m-2TMB-5 is also found to be a good beta-nucleater of PP-B. When the amount of TMB-5 is 0.3%, the notch impact strength reaches to the maxiumun vaule of 9.77 kJ·m-2, the raised amount is 40% compared with the PP-B without any nucleater. The order in efficiency of beta nucleation of PP-B is:PA-Ca>TMB-5>AA-Na.Adipates, pimelates and TMB-5 asβ-nucleaters of PP-R were studied in this thesis too. the research shows that the DSC curve of PP-R with TMB-5 as nucleater has a two peaks str-ucture while the structure of DSC curve of PP-R using the adipates and pimelates as nucleters is too weak to find. Compared the mechnical properties of PP-R modificated by PA-Ca, AA-Ca, and TMB-5, the result shows that the nortch inpact strength from 10.4 kJ·m-2 to 14.5 kJ·m-2, raised 40% when the amount of PA-Ca is 0.3% in PP-R; the strength reached 13.6 kJ·m-2, raised 30% when the amount of AA-Ca was 0.3%. When the amount of TMB-5 is 0.2%, PP-R got the maximum nortch inpact strength 10.2 kJ·m-2, raised 52%,compared the PP-R without any nucleater. Above all the order in efficiency of beta nucleation of PP-R is:TMB-5>PA-Ca >AA-Ca. Besides, the structure of TMB-5 is determined using the schemes of elementary analysis, Transform Infra-red Spectrometry (IR) and Nuclear Magnetic Resonance (NMR) etc.Furthermore, the DSC curves of polyethylene pressure pipeline (PE100) were analyzed in details, it shows that DSC can accurately determine the material of PE100. the difference between PE100 and other kinds of polyethylene was studied in details and the checkout method of chemical materials of polyethylene used for outdoor water supply pipe was found at last.The special purpose materials of Polyethylene Raised Temperature (PE-RT) were analyzed by using IR, NMR, WAXD and DSC. The difference of the spectra among PE-RT and other materials were given in detail, the results shows that pure PE-RT can be checked accurately out from various kinds of other materials with DSC and special sample preparation methods.
|
PDF Full Text Request