Citation:
FENG Jinhua, MO Zishen, CHEN Donglin. DENSITY, EQUILIBRIUM HEAT OF FUSION AND EQUILIBRIUM MELTING TEMPERATURE OF NYLON 1010[J]. Chinese Journal of Polymer Science,
1990, 8(1): 61-68.

DENSITY, EQUILIBRIUM HEAT OF FUSION AND EQUILIBRIUM MELTING TEMPERATURE OF NYLON 1010
摘要:
The density, equilibrium heat of fusion and equilibrium melting temperature of Nylon 1010 were determined by means of infrared spectrum, differential scanning calorimetry, wide angle X-ray diffraction and density measurement techniques. According to Starkweatber' s method crystalline density ρc and amorphous density ρa were estimated to be 1.098 and 1.003 g/cm3 respectively by extrapolating the straight lines of the IR absorbanee against density to zero intensity. Owing to the less intense in absorbance and less sensitive to the change in crystallinity of the amorphors band the thus obtained Pcwas too low in value.Thereby the value of the ratio Pc/Pa is far less than generally accepted mean value for most crystalline polymers.Accordingly,traditional X-ray diffraction method was used through detemining the crystalline dimension(α=4.9 .B= 5.4, C=27.8 ,α=49°β77.0°, γ=63.5°),and a rather correct value of μc or the crystal density 1.13g/cm3 was obtained.The equilibrium heat of fusion △om was estimated to be 244.0J/g plotting △Hm's of specimens with different crystallinity against their corresponding specific volumes Vspand extrapolating to completely crystalline condition (Vcsp=1/ρc As to the equilibrium melting temperature Tom,because of the easiness of recrystallization of melt crystallized Nylon 1010 specimen,the well-known Hoffman's Tm-Tc method failed in determining this value and an usually rarely used Kamide double extrapolation method was adopted.The so obtained value of Tom 487 seems to be fairly reasonable.
English
DENSITY, EQUILIBRIUM HEAT OF FUSION AND EQUILIBRIUM MELTING TEMPERATURE OF NYLON 1010
Abstract:
The density, equilibrium heat of fusion and equilibrium melting temperature of Nylon 1010 were determined by means of infrared spectrum, differential scanning calorimetry, wide angle X-ray diffraction and density measurement techniques. According to Starkweatber' s method crystalline density ρc and amorphous density ρa were estimated to be 1.098 and 1.003 g/cm3 respectively by extrapolating the straight lines of the IR absorbanee against density to zero intensity. Owing to the less intense in absorbance and less sensitive to the change in crystallinity of the amorphors band the thus obtained Pcwas too low in value.Thereby the value of the ratio Pc/Pa is far less than generally accepted mean value for most crystalline polymers.Accordingly,traditional X-ray diffraction method was used through detemining the crystalline dimension(α=4.9 .B= 5.4, C=27.8 ,α=49°β77.0°, γ=63.5°),and a rather correct value of μc or the crystal density 1.13g/cm3 was obtained.The equilibrium heat of fusion △om was estimated to be 244.0J/g plotting △Hm's of specimens with different crystallinity against their corresponding specific volumes Vspand extrapolating to completely crystalline condition (Vcsp=1/ρc As to the equilibrium melting temperature Tom,because of the easiness of recrystallization of melt crystallized Nylon 1010 specimen,the well-known Hoffman's Tm-Tc method failed in determining this value and an usually rarely used Kamide double extrapolation method was adopted.The so obtained value of Tom 487 seems to be fairly reasonable.

计量
- PDF下载量: 0
- 文章访问数: 1345
- HTML全文浏览量: 9