【摘要】：金屬制品在人們?nèi)粘Ｉ钜约敖?jīng)濟(jì)建設(shè)中占據(jù)了重要的地位,但金屬制品在儲(chǔ)存和使用過(guò)程中,非常容易受到環(huán)境中許許多多因素的影響,從而導(dǎo)致腐蝕,進(jìn)而會(huì)使金屬產(chǎn)品的顏色、光澤、外形還有性能受到損傷。傳統(tǒng)的油性防銹劑涂覆后外觀差,需后續(xù)清除。傳統(tǒng)水性防銹劑防銹性能不夠理想,且大多含有亞硝酸鹽、鉻酸鹽等有毒有害的物質(zhì),會(huì)污染生態(tài)環(huán)境,因此,研制出一種性能優(yōu)良、環(huán)保的金屬防銹劑,意義重大。硅酸鋰是一種水性防銹劑,具有良好的成膜性和成膜后的穩(wěn)定性,無(wú)毒無(wú)害。硅烷偶聯(lián)劑具有無(wú)機(jī)反應(yīng)性基團(tuán)和有機(jī)反應(yīng)性基團(tuán),可以和有機(jī)與無(wú)機(jī)材料發(fā)生化學(xué)鍵合(偶聯(lián))、交聯(lián)反應(yīng),能有效地改善防銹膜強(qiáng)度,提高涂層與基體之間的結(jié)合力。有機(jī)酸是一種有效的螯合劑,能在一定程度上起到增進(jìn)膜附著力的作用,且在較大pH值的范圍內(nèi)保持較強(qiáng)穩(wěn)定性。少量的Zn(H2PO4)2·2H2O可水解生成堿式磷酸鹽,該鹽類難溶于水,能堵塞防腐層中表面的針孔。與此同時(shí),Zn2+可同金屬基體表面的羥基反應(yīng),生成難溶的Zn(OH)2,也可堵塞表面針孔。六次甲基四胺由于靜電引力的作用,不斷趨近于金屬表面,發(fā)生物理吸附作用,而后N原子上孤對(duì)電子和金屬中的空d軌道配對(duì)成鍵即配位鍵,從而產(chǎn)生很強(qiáng)的化學(xué)吸附,可提升防銹膜物理化學(xué)性能。本文制備低濃度硅酸鋰溶液為基料、加入偶聯(lián)劑KH550、六次甲基四胺、磷酸二氫鋅、有機(jī)酸等助劑按一定比例混合反應(yīng),復(fù)配出一種具有協(xié)同作用,物理性能優(yōu)良、高附著力、防銹性能優(yōu)良的水性防銹劑。文章采用單因素實(shí)驗(yàn)和正交實(shí)驗(yàn),考察硅酸鋰溶液的添加量和模數(shù),磷酸鹽、有機(jī)酸、胺類化合物添加量,硅烷偶聯(lián)劑體系添加量及組成對(duì)防銹劑防銹性能的影響。實(shí)驗(yàn)確定最優(yōu)配方:在水性防銹劑200ml中:硅酸鋰溶液84g,M硅酸=4.0;六次甲基四胺0.03g,磷酸二氫鋅0.025g,硅烷偶聯(lián)劑KH550體系(VKH550:V水:V乙醇1:8:1)0.25ml,有機(jī)酸0.02ml。以此配方形成的防銹膜,固化速度快,成膜性能好,附著力高,防銹性能優(yōu)良。按上述配方制備出防銹劑,試件在其中浸泡5min后取出,于25℃條件下干燥 120min 后,用含有 41g/L CuSO4·5H2O、35g/L NaCI、13ml/LHCI混合制備的CuSO4點(diǎn)滴,233 s后才出現(xiàn)腐蝕痕跡,用3%鹽水浸泡62min才出現(xiàn)腐蝕痕跡,用中性鹽霧實(shí)驗(yàn)361h才出現(xiàn)腐蝕痕跡,防銹性能優(yōu)良。通過(guò)對(duì)試件和防銹劑的膜干燥時(shí)間(表干和實(shí)干)、鉛筆硬度、附著力、柔韌性等性能進(jìn)行檢測(cè),通過(guò)環(huán)境掃描電鏡SEM分析、紅外光譜分析(反射吸收紅外光譜RA-IR)、熱重分析、X射線能譜法(EDS)分析表征,該防銹劑固化的膜具有很好的對(duì)金屬的附著力、潤(rùn)濕性、具有優(yōu)良的硬度、柔韌性,快干性,物理性能優(yōu)良。
[Abstract]:Metal products play an important role in people's daily life and economic construction, but in the process of storage and use, metal products are very vulnerable to the influence of many factors in the environment, which leads to corrosion. In turn, metal products will be damaged in color, luster, shape and performance. Traditional oil anti-rust agent after coating poor appearance, need to be removed. The antirust performance of traditional water-based antirust agent is not ideal enough, and most of them contain toxic and harmful substances such as nitrite, chromate and so on, which will pollute the ecological environment. Therefore, it is of great significance to develop a kind of metal antirust agent with excellent performance and environmental protection. Lithium silicate is a kind of water-borne antirust agent, it has good film-forming property and stability after film-forming, it is non-toxic and harmless. Silane coupling agent has inorganic reactive group and organic reactive group, can be chemically bonded (coupled) with organic and inorganic materials, cross-linking reaction, can effectively improve the strength of antirust film, improve the bonding force between coating and matrix. Organic acid is an effective chelating agent, which can enhance the adhesion of membrane to a certain extent, and maintain a strong stability in the range of larger pH value. A small amount of Zn (H2PO4) 2 2H2O can be hydrolyzed to form basic phosphate, which is insoluble in water and can clog the pinholes on the surface of the coating. At the same time, Zn2 reacts with hydroxyl groups on the surface of metal matrix to form insoluble Zn (OH) 2, which can also block the surface pinholes. Due to the action of electrostatic gravity, hexamethylenetetramine (hexamethylenetetramine) is getting closer to the surface of metal and physical adsorption occurs. Then, the pair of electrons on the N atom and the empty d orbitals in the metal are paired together, that is, the coordination bond, resulting in a strong chemisorption. It can improve the physical and chemical properties of antirust film. In this paper, the low concentration lithium silicate solution was prepared as the base material, the coupling agent KH550, hexamethylenetetramine, zinc dihydrogen phosphate, organic acid and other auxiliaries were mixed in a certain proportion to give a kind of synergistic effect, good physical properties and high adhesion. A water-borne antirust agent with excellent antirust properties. In this paper, the effects of addition and modulus of lithium silicate solution, phosphate, organic acid, amine compound, silane coupling agent system and composition on antirust performance of antirust agent were investigated by single factor experiment and orthogonal experiment. The optimum formula was determined as follows: in water-borne antirust agent 200ml: lithium silicate solution 84g, M silicic acid = 4.0; Hexamethylenetetramine 0.03g, zinc dihydrogen phosphate 0.025g, silane coupling agent KH550 system (VKH550:V water: v-ethanol 1:8:1) 0.25 ml, organic acid 0.02 ml. The anti-rust film formed by this formula has the advantages of high curing speed, good film-forming performance, high adhesion and good rust-proof property. After soaking in 5min and drying 120min at 25 鈩，

本文編號(hào)：2468469