Synthesis Of Water-borne Polyurethane And Basic Study Of Thin Walled Tubulars Dipped From Thickened Polyurethane Latex

Thin walled tubulars articles of the thermoplastic elastomer are known in the art to provide strong ,thin, flexible protective barriers. Protective barriers having these characteristics are particularly useful to protect skin surfaces from unwanted contact or contamination and ,yet ,to preserve sensitivity of touch ,as with condoms ,gloves and finger cots used in medical examination . So it was used widely by surgeons who need tactile feel and resilient glove material for their delicate operations, patients and gerneral people.Natural rubber from latex has been the most important material of choice for the thin walled tubulars for a long time . However because of natural rubber's allergic reaction, scientists tried to use other materials such as synthetic rubbers and polyurethane to manufacture thin walled tubulars. Now the most popular method to manufacture polyurethane(PU) thin walled articles is dipping from organic solution. But the organic solvent will result in high cost and environmen pollution . The waterborne PU is a good candidate for produce thin walled tubulars, but it has not been applied for its poor viscosity and bad processibility.The problem was solved by a new method in this paper. A kind of waterborne PU with good properties has been synthesised. And the thin Walled Tubulars were manufactured by dipping a suitably shaped former into the thickened PU latex. Thismethod could provide good storage stability and processibility.In this paper a series of PUT water-borne PU were synthesized on the basis of toluene diisocyanate(TDI), poly(tetrahydrofuran)(PTMG) and ethylene diamine(ED), 2,2-Bis(hydroxyl methyl) propionic acid (DMPA) etc. The effect of thickener content on the properties of water-borne polyurethane was also discussed. To study the relationship between structures and properties, fourier transform infrared spectroscopy (FTIR), differential Scanning calorimetry(DSC) were used. The results showed that test on mechanical properties and water contact angles revealed their good mechanical properties and hydrophilicity. The sample thickened with 1.10% thickener exhibited much higher mechanical properties(tensile strength:29.71Mpa) and viscosity(433cp) than the original sample. Blood compatibility was evaluated by means of hemolysis test and platelet adhesion test, which reveal its good biocompatibility. The indexes of manufactured condom match the GB standards and clinical need. It showed that the method had the possibility to produce the thin walled articles.The color of PUT changed to yellow after exposing under daylight for four months. So a series of PUI water-borne polyurethane were synthesized on the basis of isophorone diisocyanate (IPDI), poly (oxypropylene) glycol (PPG) and 2,2-Bis(hydroxyl methyl) propionic acid (DMPA) etc. Fourier transform infrared spectroscopy (FTIR), differential Scanning calorimetry (DSC) were used to study the relationship between structures and properties. The results showed that mechanical properties of PUI increased with the amount of thickener then decreased quickly. The sample with 0.05% thickener had good mechanical properties (tensile strength: 32.33MPa), hydrophilicity and blood compatibility. However the thickened latex had bad processibility.On the basis of the reaserch of PUI, we designed a kind of environment-friendly biodegradable polyurethane(PCE-PU) which was synthesised by isophorone diisocyanate (IPDI), polyethylene glyol) (PEG) and -caprolactone (CL). The change of weight loss, molecular weight and water contact angle were studiedduring the degradation. The pH value of solution during degradation was also tested. The results showed that the PCE-PU degraded quickly, its molecular weight decreased about 90% after 10 days; and weight loss was above 80% after 13 days.