林产化学与工业
林產化學與工業
림산화학여공업
CHEMISTRY AND INDUSTRY OF FOREST PRODUCTS
2015年
2期
25-30
,共6页
水性异氰酸酯木材胶黏剂%耐久性%加速老化%湿热老化
水性異氰痠酯木材膠黏劑%耐久性%加速老化%濕熱老化
수성이청산지목재효점제%내구성%가속노화%습열노화
aqueous polymer isocyanate wood adhesive%durability%accelerated aging%hydrothermal aging
通过红外、热重和压剪强度分析,对水性异氰酸酯( API)木材胶黏剂在加速老化处理1~7个周期( A1~A7)和湿热老化处理1~7个周期( H1~H7)的耐久性进行了研究。红外分析表明:未处理的API胶膜( S)含有大量的异氰酸酯基团,A1~A7的API胶膜中异氰酸酯基团全部消失,H1~H3的API胶膜中仍有异氰酸酯吸收峰存在,但强度减弱, H4~H7的异氰酸酯基团消失。热重分析结果表明:A1~A4胶膜的初期热稳定性优于H1~H4,5~7个周期热稳定性几乎相同。在相同质量损失下,加速老化处理API胶膜更稳定, A1~A7降解活化能不完全相同,即降解速度不同;而H1~H7胶膜的活化能几乎相同。2种处理方法胶合制品的压剪强度随时间延长逐渐降低,加速老化处理到第3个周期压剪强度仅为5.32MPa,湿热老化处理到第5个周期压剪强度降为6.92 MPa,均达不到国家标准。
通過紅外、熱重和壓剪彊度分析,對水性異氰痠酯( API)木材膠黏劑在加速老化處理1~7箇週期( A1~A7)和濕熱老化處理1~7箇週期( H1~H7)的耐久性進行瞭研究。紅外分析錶明:未處理的API膠膜( S)含有大量的異氰痠酯基糰,A1~A7的API膠膜中異氰痠酯基糰全部消失,H1~H3的API膠膜中仍有異氰痠酯吸收峰存在,但彊度減弱, H4~H7的異氰痠酯基糰消失。熱重分析結果錶明:A1~A4膠膜的初期熱穩定性優于H1~H4,5~7箇週期熱穩定性幾乎相同。在相同質量損失下,加速老化處理API膠膜更穩定, A1~A7降解活化能不完全相同,即降解速度不同;而H1~H7膠膜的活化能幾乎相同。2種處理方法膠閤製品的壓剪彊度隨時間延長逐漸降低,加速老化處理到第3箇週期壓剪彊度僅為5.32MPa,濕熱老化處理到第5箇週期壓剪彊度降為6.92 MPa,均達不到國傢標準。
통과홍외、열중화압전강도분석,대수성이청산지( API)목재효점제재가속노화처리1~7개주기( A1~A7)화습열노화처리1~7개주기( H1~H7)적내구성진행료연구。홍외분석표명:미처리적API효막( S)함유대량적이청산지기단,A1~A7적API효막중이청산지기단전부소실,H1~H3적API효막중잉유이청산지흡수봉존재,단강도감약, H4~H7적이청산지기단소실。열중분석결과표명:A1~A4효막적초기열은정성우우H1~H4,5~7개주기열은정성궤호상동。재상동질량손실하,가속노화처리API효막경은정, A1~A7강해활화능불완전상동,즉강해속도불동;이H1~H7효막적활화능궤호상동。2충처리방법효합제품적압전강도수시간연장축점강저,가속노화처리도제3개주기압전강도부위5.32MPa,습열노화처리도제5개주기압전강도강위6.92 MPa,균체불도국가표준。
The durability of aqueous polymer isocyanate ( API) wood adhesive was studied under accelerated aging process for 1-7 cycles (A1-A7) and hydrothermal aging for 1 -7 cycles (H1 -H7) by using Fourier transform infrared spectroscopy ( FT-IR) , thermogravimetric analysis( TGA) , and compressive shear strength analysis. FT-IR analysis showed that the untreated API film( S) contained a considerable amount of isocyanate group, whereas the isocyanate groups of API films for A1 -A7 disappeared. Absorption peaks of isocyanate group of API films for H1 - H3 still existed, but the intensity weakened. The isocyanate groups of API films for H4 -H7 also disappeared. TGA analysis showed that thermal stabilities of A1 -A4 in the initial stage were superior to those of H1-H4, but they were almost the same in the 5-7 cycles. Under the same weight loss, the API films with accelerated aging process were more stable, and the degradation activation energies of A1 -A7 were not exactly the same, namely, the degradation rates were different. However, the activation energies of H1 -H7 were almost the same. The compressive shear strengths of glued products treated in the two methods were gradually decreased. The compressive shear strengths of the API films with accelerated aging process for the third cycle was 5. 32 MPa and that of sample with hydrothermal aging for the fifth cycle was 6. 92MPa. They did not meet the national standards.