【摘要】：低溫快速固化粉末涂料近年來成為各企業(yè)或研究單位主要的研發(fā)課題,粉末涂料實現(xiàn)低溫快速固化意義重大,不但節(jié)能降耗,降低成本,而且會拓寬應(yīng)用領(lǐng)域,使得這種新型的涂料取代傳統(tǒng)涂料的速度加快。本文從粉末涂料所用的聚酯樹脂入手,通過引入新型單體對制備聚酯樹脂的配方和工藝進(jìn)行改進(jìn),提升聚酯樹脂的主鏈柔韌性和端基活性,在合成后期添加特殊效果的促進(jìn)劑,有效降低了粉末涂料的固化反應(yīng)溫度,縮短了固化反應(yīng)時間,使傳統(tǒng)的以異氰脲酸三縮水甘油酯作為固化劑的粉末涂料,在200℃溫度下放置10分鐘的固化條件降低到130℃放置20分鐘。并考察了聚酯樹脂的各項性能及其在粉末涂料中的表現(xiàn),如涂層外觀,沖擊性能,耐人工老化性等性能。經(jīng)過各種實驗對比,以TGIC為固化劑的粉末涂料用聚酯樹脂在酸價40-45mgKOH/g時會表現(xiàn)出較好的低溫快速固化傾向,主要原材料有對苯二甲酸,己二酸,2-丁基-2-乙基-1,3-丙二醇,1,4-環(huán)己烷二甲酸,1,6-己二醇,間苯二甲酸,三羥甲基丙烷,反丁烯二酸,新戊二醇,并輔以丁基錫酸,復(fù)合抗氧劑,固化促進(jìn)劑,得到了酸值42.4mgKOH/g,熔融粘度3160mPa.s,軟化點(diǎn)111℃,外觀為無色透明的顆粒。按照聚酯樹脂與TGIC的92:8的固化比例,配以顏料、填料、助劑等通過混合,熔融擠出,研磨,過篩,噴涂和烘烤,在130℃烘烤20分鐘時得到較滿意的粉末涂層。對上述配方合成的聚酯樹脂,通過GPC凝膠色譜,DSC差式掃描量熱儀,近紅外及中紅外對聚酯樹脂進(jìn)行表征,測試分析后,得出數(shù)均分子量是5519,重均分子量是8425,分子量分布寬度是1.53,分子量分布寬度適中。通過DSC測得玻璃化溫度是58.8℃,具有較好的儲存穩(wěn)定性。對制備的粉末涂層通過人工加速老化試驗,考察涂層的失光,粉化以及褪色情況,該粉末涂料制備的粉末涂層達(dá)到了粉末涂料的優(yōu)級標(biāo)準(zhǔn)。
[Abstract]:In recent years, low temperature and fast curing powder coatings have become the main research and development topics of various enterprises or research units. It is of great significance to realize low temperature rapid curing of powder coatings, which not only saves energy and reduces costs, but also widens the application fields. The speed of replacing the traditional coatings with this new coating is accelerated. Starting with the polyester resin used in powder coating, the formula and process of preparing polyester resin were improved by introducing new monomer to improve the flexibility and terminal group activity of the main chain of polyester resin, and the accelerator of special effect was added in the later stage of synthesis. The curing reaction temperature of powder coating was reduced effectively, the curing time was shortened, and the traditional powder coating with triglycidyl isocyanurate as curing agent was made. The curing conditions at 200 鈩，

本文編號：2125581