摘 要: 針對廢舊風電葉片粉體材料(WWTB)回收加工高值化利用問題,以WWTB(平均粒徑尺寸<2 mm)為原料,采用三種不同的改性劑對其進行活化改性修飾,選擇出較佳的改性劑及用量,得到改性修飾廢舊風電葉片粉體材料(GWWTB)。采用熔融共混方式制備改性修飾廢舊風電葉片粉體/聚丙烯復合材料(GWWTB/PP),考察GWWTB含量對GWWTB/PP復合材料力學性能、熱穩(wěn)定性能、潤濕性能和斷裂面微觀形貌的影響。結果表明:采用質量分數(shù)4wt%的Z-6173改性效果最佳,活化指數(shù)提高了78.6%。當GWWTB含量質量分數(shù)為6wt%時,GWWTB/PP復合材料熱穩(wěn)定性最高,拉伸強度和沖擊強度最大,熱失重5%分解溫度提高了11.7%,拉伸強度和沖擊強度分別提高了22.89%和178.54%,GWWTB/PP復合材料的潤濕性能隨著GWWTB含量的增加而提高,GWWTB/PP復合材料親水性增強。
關 鍵 詞:廢舊風電葉片粉體材料; 改性劑; 聚丙烯; 力學性能; 潤濕性能
中圖分類號:TQ314.262文獻標志碼: A文章編號: 1004-0935(20202024)0×9-1351-04
風電葉片作為風電能源產(chǎn)業(yè)裝置必不可少的核心部件之一,一般的使用壽命為20~30年,在未來的十幾年內,將會出現(xiàn)風電葉片的“下線潮”,風電葉片復合材料的回收問題亟待解決[1-3]。目前國內主要以焚燒和填埋的方式處理[4-5],這兩種回收方法都很難將廢棄物再資源化,廢棄物焚燒和填埋處置造成大量可循環(huán)資源的流失,而且還會占用土地資源,對環(huán)境造成二次污染,周邊可供處置的土地面積大量減少[6-7]。物理回收方法相對于前兩種回收方式具有低碳環(huán)保、節(jié)約資源、操作簡單的優(yōu)勢,它主要是通過研磨粉碎方式獲得復合填料,所以常用于廢棄材料的回收和處理[8]。
基于健全風電產(chǎn)業(yè)全生命周期循環(huán),為了將WWTB清潔回收和高值化利用,本文將對WWTB進行改性修飾,選擇出較佳的改性劑及含量,然后制備GWWTB/PP復合材料,研究GWWTB含量對其力學性能、熱穩(wěn)定性能和潤濕性能的影響。同時將WWTB填充引入PP體系中文章鮮有報道,可以為提高PP性能提供新思路和新方法。
1 實驗部分
1.1 實驗材料
WWTB;γ-氨丙基三乙氧基硅烷(KH550,上海耀華化工廠);γ-(2,3-環(huán)氧丙氧)丙基三甲氧基硅烷(KH560,上海耀華化工廠);Z-6173(美國道康寧公司);鄰苯二甲酸二丁酯(DBP,天津市大茂化學試劑廠);聚丙烯(PP,北歐化工)。
1.2WWTB改性修飾及GWWTB/PP復合材料制備
將WWTB通過濕法改性與含有不同官能團的改性劑發(fā)生化學反應得到GWWTB。將GWWTB與PP采用熔融共混的方式擠出造粒,得到GWWTB/PP復合原料,進行性能測試與表征。
1.3測試與表征
質量法測定活化指數(shù);用IR Prestige-21型紅外光譜儀分析WWTB改性修飾前后官能團結構變化;用Q50型熱重分析儀分析GWWTB/PP復合材料熱穩(wěn)定性;拉伸強度和沖擊強度分別按照GB/T 1040.1—2006、GB/T 1843—2008測試;使用JC2000D8型接觸角測量儀對樣品進行水接觸角測量;使用EVO MA-10型掃描電子顯微鏡分析GWWTB/PP復合材料標準測試樣條拉伸斷裂面微觀形貌。
2結果與討論
2.1 WWTB改性修飾研究
2.1.1活化指數(shù)
改性劑可以改變粉體表面性質,以改善WWTB與其他材料間的相容性,通過活化指數(shù)可以簡單直觀地反映樣品的改性修飾效果[9]。改性劑質量分數(shù)對WWTB活化指數(shù)影響見圖1,WWTB經(jīng)過質量分數(shù)4% Z-6173改性修飾活化指數(shù)最高,從未改性的3%提高到81.6%;說明經(jīng)過改性修飾后,WWTB的疏水性有所提高,與其他材料或者基體相容性更好。這與改性劑中的疏水基團有關,疏水基團與WWTB結合導致復合材料呈現(xiàn)良好的疏水性。
2.1.2表面結構分析
圖2為Z-6173改性修飾前后紅外光譜圖,Z-6173紅外光譜中2 960 cm-1處為烷基官能團,1 080 cm-1和808 cm-1處為Si-O鍵特征吸收峰,改性修飾后紅外光譜在2 962.66 cm-1處出現(xiàn)-CH的反對稱伸縮振動峰,在1 263.37 cm-1和1 035.77 cm-1處出現(xiàn)脂肪醚C-O鍵吸收峰。說明Z-6173中的Si-O鍵與WWTB中的環(huán)氧基團發(fā)生開環(huán)交聯(lián)反應,烷基官能團也有效與WWTB相結合,Z-6173改性劑的引入提高了WWTB與其他材料的相容性問題,使其與其他基體材料能夠更好相容。
2.2 GWWTB/PP復合材料研究
2.2.1 GWWTB質量分數(shù)對GWWTB/PP復合材料熱穩(wěn)定性影響
圖3為GWWTB質量分數(shù)對GWWTB/PP復合材料熱失重影響。PP初始分解溫度為341.0 ℃,PP熱失重5%,分解溫度為380.6 ℃。當GWWTB質量分數(shù)為6%時,GWWTB/PP復合材料初始分解溫度最高為348.0 ℃,熱失重5%,分解溫度最高為425.1 ℃,此時GWWTB/PP復合材料的熱穩(wěn)定性最好,兩者相容性最好,GWWTB可以提高GWWTB/PP復合材料的熱穩(wěn)定性。GWWTB/PP復合材料的殘余量應該歸因于GWWTB中的玻璃纖維含量,隨著GWWTB含量增加,GWWTB/PP復合材料殘余量增大。
2.2.2 GWWTB質量分數(shù)對GWWTB/PP復合材料力學性能影響
GWWTB質量分數(shù)對GWWTB/PP復合材料力學性能影響見圖4。
當GWWTB質量分數(shù)為6%時,拉伸強度最高為34.63 MPa,沖擊強度最高為12.59 kJ·m-2,分別提高了22.89%和178.54%。說明GWWTB中的玻璃纖維可以增強PP,PP與GWWTB相容性較好,隨著GWWTB含量的增大,會有更多的粉體來承擔基體傳遞的載荷,GWWTB/PP復合材料強度會增加,但隨著粉體質量分數(shù)大于6%時,粉體會出現(xiàn)團聚現(xiàn)象,不能很好地分散在PP表面,不能形成有效包覆,兩者相容性變差,從而導致GWWTB/PP復合材料力學性能下降。
2.2.3 GWWTB質量分數(shù)對GWWTB/PP復合材料斷裂面微觀形貌影響
GWWTB質量分數(shù)對GWWTB/PP復合材料斷裂面SEM影響見圖5。
隨著GWWTB少量加入,GWWTB/PP復合材料測試樣條拉伸斷裂面比較粗糙,斷面呈褶皺狀,表明其拉伸斷裂為較強的韌性斷裂,因此GWWTB/PP復合材料有很高的拉伸強度。當GWWTB添加質量分數(shù)超過6%后,GWWTB/PP復合材料拉伸斷裂面開始變得逐漸光滑平整,斷裂面褶皺變小,表明GWWTB/PP復合材料韌性斷裂減弱,分散相開始增多,說明GWWTB與PP相容性開始變差,從而導致GWWTB/PP復合材料的力學性能降低。
2.2.4 GWWTB質量分數(shù)對GWWTB/PP復合材料潤濕性能影響
采用熱壓法將GWWTB/PP原料制成復合薄膜,測定其水接觸角,從而判斷GWWTB/PP復合薄膜的潤濕性能。GWWTB質量分數(shù)對GWWTB/PP復合材料潤濕性能影響見圖6。
隨著GWWTB質量分數(shù)的增加,GWWTB/PP復合薄膜的接觸角逐漸變小,從110.72°降低到64.52°,說明GWWTB/PP復合薄膜潤濕性能增強,GWWTB/PP復合薄膜從疏水性變成親水性。原因可能在于隨著GWWTB含量的增加,GWWTB中的改性劑具有較低的表面能,較高的潤濕能力,從而提高非均質材料之間的相容性和分散性,使兩者緊密結合,從而完成非均質材料之間的偶聯(lián)過程,使GWWTB/PP復合薄膜表面親水,表面張力變大。
3 結論
采用含有不同官能團的改性劑對WWTB進行改性修飾,Z-6173改性修飾效果最好,較佳質量分數(shù)為4%。當GWWTB質量分數(shù)為6%時,GWWTB/ PP復合材料熱穩(wěn)定性、力學性能最好;熱失重5%時分解溫度提高了11.7%,拉伸強度提高了22.89%,沖擊強度提高了178.54%;隨著GWWTB含量的增加,GWWTB/PP復合薄膜接觸角由110.72°降低到64.52°,GWWTB/PP復合材料從疏水性材料變成親水性材料。
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Research on Mechanical Properties and Wettability of Waste
Wind Turbine Blade Powder/Polypropylene Composite
YU Meng1a, ZHANG Ai-ling1,*a, XING Zuo-xia2b, ZHANG Yu-qing1a, GE Jing-yi1a,
FAN Yu-ting1a, LI Li-shi1a, WANG Rui-han1a, JIN Yao-jun1a
(1a.Schoolof Environmental and Chemical Engineeringof Shenyang University of Technology, Liaoning Shenyang 110870,China;
2b. New Energy Research Instituteof,Shenyang University of Technology, ShenyangLiaoning Shenyang110870,,China)
Abstract:Aiming at the high value utilization of waste wind turbine blade powder material (WWTB) recycling and processing, WWTB (average particle size < 2 mm) was used as raw material, it was activated and modified by three different modifiers, and the better modifier and dosage were selected to obtain modified waste wind turbine blade powder material (GWWTB).The modified waste wind turbine blade powder/polypropylene composite (GWWTB/PP) was prepared by melt blending. The effects of GWWTB content on the mechanical properties, thermal stability, wettability and fracture surface morphology of GWWTB/PP composite were investigated.The results showed that mass fraction 4% Z-6173 had the best modification effect, the activation index was increased by 78.6%.When the mass fraction of GWWTB was 6%, the thermal stability, tensile strength and impact strength of GWWTB/PP composite material were the best. The thermal decomposition temperature of 5% weight loss was increased by 11.7%,the tensile strength and impact strength were increased by 22.89% and 178.54%, respectively.using different modifying agents as raw materials, the modified waste wind turbine blade powder material (GWWTB) was obtained by selecting the best modifier and dosage. Modified waste wind turbine blade powder/polypropylene composite (GWWTB/PP) was prepared by melt blending method. The effects of GWWTB content on mechanical properties, thermal stability, wetting property and fracture surface microstructure of GWWTB/PP composite material were investigated. The results show that 4wt% Z-6173 has the best modification effect, the activation index is increased by 78.6%. When the content of GWWTB is 6wt%, the thermal stability, tensile strength and impact strength of GWWTB/PP composite material are the best. The thermal decomposition temperature of 5% weight loss is increased by 11.7%,the tensile strength and impact strength are increased by 22.89% and 178.54%, respectively. The wettability of GWWTB/PP composite material increases increased with the increase of GWWTB content, enhancing the hydrophilicity of GWWTB/PP composite material.
Key words:Waste wind turbine blade powder material;Modifying agent; Polypropylenel; Mechanical property; Wetting property