摘要:
Disclosed is a copolyester resin composed mainly of terephthalic acid, ethyleneglycol, 1,4-cyclohexanedimethanol, polyethyleneglycol bisphenol-A and a multifunctional monomer. According to the current invention, the multifunctional monomer and polyethyleneglycol bisphenol-A are additionally copolymerized along with 1,4-cyclohexanedimethanol, whereby the resultant copolyester resin can have low haze and high melt viscosity and melt strength, with superior moldability due to low melt pressure. In addition, extrusion blow molded articles and profile extruded articles, such as bottles and tubes, are provided by use of the copolyester resin having superior properties.
摘要:
Disclosed is a method for preparing polyester resins copolymerized with 1,4-cyclohexanedimethanol. In the preparation method, ethylene glycol and 1,4-cyclohexanedimethanol are fed with the molar ratio of the whole glycol component to terephthalic acid ranging from 1.3 to 3.0, and then esterified. Then, the esterified reaction product is polycondensed in the presence of titanium-based compound as a polycondensation catalyst and carboxy phosphonic acid typed compound represented by formula I below as a stabilizer, to give the polyester resins of the present invention having excellent clarity and good color: wherein R1, R2 and R3, which are the same or different, each being selected from the group consisting of hydrogen, alkyl groups having 1 to 10 carbon atoms, cycloalkyl groups having 1 to 10 carbon atoms and aryl groups having 6 to 10 carbon atoms; and R is selected from the group consisting of alkylene groups having 1 to 10 carbon atoms, cycloalkylene groups having 1 to 10 carbon atoms, and arylene groups having 6 to 10 carbon atoms.
摘要:
Disclosed is a method for preparing polyester resins copolymerized with glycol for modification such as 1,4-cyclohexanedimethanol, in which the content of said glycol ingredient for modification ranges from 20 to 80 mol % of the total glycol content. Dicarboxylic acid such as terephthalic acid is esterified with ethylene glycol and said glycol for modification. The esterification product is subjected to polycondensation in the presence of a titanium dioxide/silicon dioxide coprecipitate catalyst, said catalyst being in the form of 4% or less strength by weight suspension in glycol. The copolyester prepared as above shows excellent transparency and color properties in addition to being produced at high efficiency.
摘要:
The present invention relates to a pipeline examination apparatus for Direct Current Voltage Gradient (DCVG) and Closed Interval Potential Survey (CIPS) methods. The pipeline examination apparatus of the present invention detects and analyzes at least one electrode signal while supplying an anticorrosive current to a buried pipeline by switching on and off the anticorrosive current at predetermined intervals. The pipeline examination apparatus includes a signal detection unit and a measurement unit. The signal detection unit detects the electrode signal including a DCVG electrode signal and/or a CIPS electrode signal. The measurement unit receives the electrode signal from the signal detection unit and analyzes the electrode signal. The measurement unit includes a measurement method selection unit, a control unit, a storage unit, an analysis unit and a display unit.
摘要:
The present invention relates to a pipeline examination apparatus for Direct Current Voltage Gradient (DCVG) and Closed Interval Potential Survey (CIPS) methods. The pipeline examination apparatus of the present invention detects and analyzes at least one electrode signal while supplying an anticorrosive current to a buried pipeline by switching on and off the anticorrosive current at predetermined intervals. The pipeline examination apparatus includes a signal detection unit and a measurement unit. The signal detection unit detects the electrode signal including a DCVG electrode signal and/or a CIPS electrode signal. The measurement unit receives the electrode signal from the signal detection unit and analyzes the electrode signal. The measurement unit includes a measurement method selection unit, a control unit, a storage unit, an analysis unit and a display unit.