發(fā)布時間：2018-03-14 15:43

  本文選題：PVC涂層膜結(jié)構(gòu)材料　切入點：人工加速老化　出處：《東華大學》2015年碩士論文　論文類型：學位論文

【摘要】：隨著聚氯乙烯（PVC）涂層膜結(jié)構(gòu)材料的不斷發(fā)展，因其空間形式獨特、價格低廉、能源損耗低、使用性能優(yōu)良等特點，現(xiàn)已被廣泛應(yīng)用于展覽、體育、交通、休閑等建筑中。國外學者研究發(fā)現(xiàn)，PVC涂層膜結(jié)構(gòu)材料在戶外使用條件下易受陽光中紫外線的作用而發(fā)生老化，且外界機械應(yīng)力的作用也會引起材料內(nèi)部物理、化學結(jié)構(gòu)發(fā)生變化，從而改變材料的光氧老化速度、破壞材料的強力、縮短材料的老化時間，最終導(dǎo)致膜結(jié)構(gòu)材料失去使用性能。因此，有必要對應(yīng)力作用下PVC涂層膜結(jié)構(gòu)材料的老化性能進行研究。本課題采用了人工加速老化和大氣自然老化兩種試驗方法，研究了不同應(yīng)力作用下PVC涂層膜結(jié)構(gòu)材料的光氧老化性能。 本課題分別在無應(yīng)力（0%）以及5%、10%、20%三種應(yīng)力載荷作用下，采用人工加速老化和大氣自然老化方法對老化試樣進行了光氧老化試驗。并對老化試樣進行了表觀顏色（黃度指數(shù)、白度值）、力學性能（斷裂強力、斷裂伸長）等宏觀檢測，對試樣整個老化過程中性能的變化有了較整體的了解。同時也對老化試樣進行了掃描電鏡（SEM）、傅里葉變換紅外光譜（FTIR）等微觀檢測。既研究了不同應(yīng)力作用下膜結(jié)構(gòu)材料的光氧老化性能，又比較了不同應(yīng)力作用下人工加速老化和大氣自然老化之間的相關(guān)性。 研究發(fā)現(xiàn)，隨著老化時間的增加，黃度指數(shù)逐漸增加，白度值逐漸下降，且應(yīng)力載荷水平越大，黃度指數(shù)增加的越多，白度值下降的也越多，即老化程度越大。結(jié)合掃描電鏡觀察可知，隨著老化時間和應(yīng)力載荷作用的增加，試樣涂層表面龜裂現(xiàn)象愈發(fā)明顯，又在人工加速老化試驗中，5%應(yīng)力作用下老化達到1000h時，PVC涂層表面就出現(xiàn)了剝離現(xiàn)象，這更加說明應(yīng)力作用加速了表面涂層的開裂。在力學性能方面，無論人工加速老化還是大氣自然老化，不同應(yīng)力作用下斷裂強力保持率和斷裂伸長保持率變化都不是很顯著，而表觀顏色和表面形態(tài)變化卻相當顯著，這說明應(yīng)力作用下PVC涂層膜結(jié)構(gòu)材料的老化首先發(fā)生在表面PVC涂層，其次為基布。紅外光譜分析表明，不同應(yīng)力作用下PVC涂層膜結(jié)構(gòu)材料的光氧老化機理沒有發(fā)生變化。 由于人工加速老化方法可以縮短老化試驗周期，但人工加速老化得到的老化試驗結(jié)果與大氣自然老化的結(jié)果是否一致呢？為此，我們進行了應(yīng)力作用下PVC涂層膜結(jié)構(gòu)材料人工加速老化和大氣自然老化試驗結(jié)果之間的相關(guān)性分析。分析發(fā)現(xiàn)，兩種老化形式下斷裂強力保持率、斷裂伸長保持率、羰基指數(shù)的變化趨勢基本一致，但在累積紫外輻照能相同條件下，老化性能存在一定的差異，即不符合互易定律，從而驗證了互易定律的失效性。然而兩種老化形式白度值的變化差異最明顯，即互易定律對此不適用，由此以白度值為例建立了人工加速老化與大氣自然老化之間的相關(guān)性。Schwarzschild定律是在互易定律的基礎(chǔ)上引入了常數(shù)p，即Ipt常數(shù)（當紫外輻照強度I的p次方與老化時間t的乘積一定時，，材料的光氧老化效果是等效的）。試驗發(fā)現(xiàn)：在兩種老化形式下,當p=0.87時,人工加速老化和大氣自然老化之間有較好的相關(guān)性。然后根據(jù)Schwarzschild定律對兩種老化形式下試樣的白度值進行擬合并進行修正,再對修正后的白度值進行了線性擬合,最終得到試樣白度值與紫外輻照強度以及老化時間之間的關(guān)系方程：y=78.23-0.23x式中,x=I0.87t,I為紫外輻照強度,t為老化時間。 上述方程反映了擬合修正后白度值與紫外輻照強度以及老化時間的關(guān)系,通過方程可以看出,當p=0.87時,應(yīng)力作用下PVC涂層膜結(jié)構(gòu)材料的人工加速老化與大氣自然老化間具有較好的相關(guān)性。
[Abstract]:With the continuous development of polyvinyl chloride (PVC) coated membrane material, because of its unique space form, low cost, low energy consumption, the use of excellent performance characteristics, has been widely used in the exhibition, sports, traffic, leisure and other buildings. Foreign researchers found that the PVC coated membrane material used in the open air condition by ultraviolet light in sunlight and effect of aging, and the effect of external mechanical stress can also cause physical material, chemical structure changes, thus changing the aging speed of the material, the fracture strength, shorten the aging time of the material, resulting in membrane structure lose performance. Therefore, it is necessary to study the aging performance of PVC coated membrane material under different loads. This paper adopts two kinds of test methods of natural aging and artificial accelerated aging atmosphere, studied the stress under the action of PVC coating The optical oxygen aging properties of the film structure material.
This paper respectively in non stress (0%), 5%, 10%, 20% and three kinds of effects of stress load, using artificial accelerated aging and natural aging methods of atmospheric photooxidation aging test on aging and the aging of specimens. The specimens were apparent color (yellow index, whiteness, mechanical) properties (tensile strength, elongation at break) macro detection, change of the whole sample in the process of aging performance have a more overall understanding. At the same time were analyzed by scanning electron microscope (SEM), the aging of Fourier transform infrared spectroscopy (FTIR) micro detection. Not only studies the different light aging properties of membrane structure the material under the action of stress, and compare the different aging and natural aging of the correlation between the atmosphere accelerated under the action of force.
The study found that with the increase of aging time, the yellowness index increased gradually, the whiteness values decreased gradually, and the stress load level increases, the yellowness index increased, whiteness values decreased more and more, the aging degree is greater. Observation with scanning electron microscope, with the aging time and increase the role of force load, specimen coating surface cracking phenomenon more obvious, and in the accelerated aging test, 5% stress aging at 1000h PVC coating surface appeared peeling phenomenon, which further indicates that stress accelerated the cracking of surface coatings. In terms of mechanical properties, both artificial accelerated aging or atmospheric ageing under different stresses, breaking strength and breaking elongation rate changes are not very significant, and the apparent change of color and surface morphology is quite significant, indicating that PVC coated membrane material under the action of force The aging process first occurred on the surface PVC coating, followed by the base cloth. The infrared spectrum analysis showed that the mechanism of photooxidative aging of PVC coated membrane structure did not change under different stress.
Because the artificial accelerated aging method can shorten the aging period, but accelerated aging aging test results obtained with atmospheric ageing results are consistent? Therefore, we analyzed the correlation between the stress of PVC coated membrane material of artificial accelerated aging and atmospheric ageing test results. Analysis showed that the two kinds of aging under the form of breaking strength retention rate, breaking elongation, the change trend of carbonyl index is consistent, but when the cumulative UV radiation energy under the same conditions, there are some differences between the aging performance, that is not in conformity with the law of reciprocity, which verified the failure law of reciprocity. However, two aging changes form white value difference the most obvious, namely the law of reciprocity are not applicable, the accelerated aging.Schwarzschild correlation between aging and natural atmosphere of the establishment as an example to white value The law is a constant P is introduced based on the reciprocity law, namely Ipt (product of P square constant when ultraviolet irradiation intensity I and t aging time when light oxygen material aging effect is equivalent). Experiment results showed that: in the two kinds of aging form, when p=0.87, the accelerated aging and between atmospheric ageing have good correlation. Then according to the Schwarzschild law of whiteness of two kinds of aging form values of samples were fitted with modified, the whiteness of the corrected values are linear fitting, finally obtained the relationship between the whiteness value and ultraviolet irradiation intensity and aging time. X=I0.87t y=78.23-0.23x, I, UV radiation intensity, t as the aging time.
The above equation reflects the relationship between the corrected whiteness value and the UV irradiation intensity and aging time. It can be seen from the equation that when p=0.87 is applied, the accelerated aging of PVC coated membrane structure material has good correlation with the natural weathering.

【學位授予單位】：東華大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TS106;TB33

【參考文獻】

相關(guān)期刊論文 前10條

1 邱文燦;楊旭東;丁辛;胡淳;;PVC涂層膜材料老化性能研究的進展[J];產(chǎn)業(yè)用紡織品;2009年10期

2 王春川;;人工加速光老化試驗方法綜述[J];電子產(chǎn)品可靠性與環(huán)境試驗;2009年01期

3 張三平,蕭以德,朱華,程學群,潘瑩,蕭_g星;涂層戶外暴露與室內(nèi)加速腐蝕試驗相關(guān)性研究[J];腐蝕科學與防護技術(shù);2000年03期

4 易洪雷;丁辛;陳守輝;;PES/PVC膜材料拉伸性能的各向異性及破壞準則[J];復(fù)合材料學報;2005年06期

5 湯寶潤,楊蓉娟,俞云龍;土工布的蠕變特性研究[J];紡織學報;1993年01期

6 儲才元,張佑霞;土工布的動態(tài)蠕變及疲勞性能[J];紡織學報;2002年01期

7 楊旭東;邱文燦;丁辛;胡淳;;紫外線輻射強度對聚丙烯長絲光氧老化的影響[J];紡織學報;2009年08期

8 邱文燦;楊旭東;丁辛;胡淳;;PVC膜材料的光氧老化性能[J];紡織學報;2010年12期

9 李英華;孫麗娜;胡曉鈞;孫鐵珩;;紅外光譜技術(shù)在環(huán)境科學中的應(yīng)用與展望[J];光譜學與光譜分析;2008年10期

10 葉苑h

本文編號：1611862