%{tishi_zhanwei}%

Light snow | floating with dark fragrance

Light snow docked at the harbor. It was not obvious to stop and go in early winter. It was another year. The summer also passed by the lotus and the autumn also passed by the cicada. Today coincides with light snow-Love's light snow is cold and will snow, and the ground is not even cold and the snow is not big." From "Qunfangpu" to Xiaoxue, the northwest wind in the vast areas of China began to become a frequent visitor, and the temperature dropped and gradually dropped below 0 ℃. But at this time, the earth is not too cold, although began to snow, but the amount of snow is not large, so called "light snow". Light snow, ancient phenology once | rainbow hidden not seen the ancients believed that the over the rainbow appeared because of the yin and yang qi between heaven and earth. at this time, yin qi was exuberant and yang qi was hidden, so "rainbow hidden not seen"; Second time | the weather rises, the earth's air falls, the sun rises in the sky, and the yin in the earth falls, resulting in heaven and earth not crossing. Lesser Snow, Human Food Age | Cured bacon folk have the custom of "pickling in winter with wind and storing to protect winter. After light snow, the temperature drops sharply and the weather becomes dry, which is a good time to process bacon. Some farmers began to make sausages and bacon, store the surplus meat, and wait until the festival to enjoy | eating glutinous rice cakes "October dynasty, glutinous rice cakes lulu roast". In ancient times, Ciba was a traditional festival offering in the southern region, and it was first used by farmers to sacrifice cattle gods. It is now popular in the southern region. It is a snack of all ethnic groups in the south. It is made of glutinous rice steamed and mashed. It is soft, glutinous, sweet, delicious and attractive. | Dried fish in the sun. Taiwan proverb: October beans are so fat that they can't see their heads. It means that "bean fish" can be caught in the cloth bag area of Jiayi County in October of the lunar calendar ". During light snow, fishermen on the south-central coast of Taiwan will start drying dried fish and storing dry food. The mullet group will come to the Taiwan Strait before and after the light snow. In addition, there will be light snow such as sailfish and sandfish. Daily health preservation | Lying up early and getting up late and waiting for the sun. Before and after the light snow, attention should be paid to "raising and storing" according to the four-hour changes ". It is appropriate to go to bed early, and it is not advisable to get up too early in the morning, especially for the elderly when the sun rises to get up again to ensure adequate sleep. | Dressing more and wearing a hat starts from the light snow solar term. The climate becomes cold, which will affect cardiovascular and cerebrovascular diseases and cause blood pressure fluctuations. Traditional Chinese medicine believes that "the head is the meeting of all yang", that is, the head is the place where all yang channels converge, and it is the most resistant to wind and cold. Therefore, everyone must wear a hat, pay attention to cold prevention and protect yang qi. When the first snow comes in winter, add thick clothes to keep warm. After eating the "three blacks" and nourishing the body and mind, the diet should also pay attention to nourishing the liver and kidney, clearing internal fire and maintaining the skin. Xiao Tai recommends the following three types of healthy black food: black sesame, black water chestnut and black soybean. Black sesame nourishes the liver and moisturizes the skin, black water chestnut, antibacterial, heat-clearing, internal fire, black beans, blood-nourishing, nourishing, and warming the body and mind. In addition, there are other black foods, such as black beans, purple rice, black peanuts, black sesame seeds, black millet, black fungus, mushrooms, seaweed, etc. It is not only rich in nutrition, but also plays an important role in anti-aging and cancer prevention. The essence of health preservation lies in nourishing the heart. The bearing of life is the body and the master of life is the heart.

20

2020

/

11

These applications of talcum powder in the plastics industry must be clear!

1、在聚丙烯树脂中的应用 滑石粉常用于填充聚丙烯。滑石粉具有薄片构型的片状结构特征,因此粒度较细的滑石粉可用作聚丙烯的补强填充剂。在聚丙烯的改性体系中,加入超细滑石粉不但能够显着的提高聚丙烯制品的刚性、表面硬度、耐热蠕变性、电绝缘性、尺寸稳定性,还可以提高聚丙烯的冲击强度。在聚丙烯中添加少量的滑石粉还能起到成核剂的作用,提高聚丙烯的结晶性,从而使聚丙烯各项机械性能提高,又由于提高结晶性,细化晶粒,亦能提高聚丙烯的透明性。 填充20%和40%超细目滑石粉的聚丙烯复合材料,不论是在室温和高温下,都能够显着提高聚丙烯的刚性和高温下的耐蠕变性能。在汽车工业中,聚丙烯添加滑石粉主要用于汽车的保险杠和仪表盘,另外还用于风扇罩、加热器罩、导管、蓄电池防热板、流体泵件等;在飞机工业中,用于冰箱门衬垫、加热器及真空泵罩、洗涤机搅拌器;在电气工业中,用于注塑成型各种仪表壳体和电气元件,在家电工业中,用于冰箱抽屉、洗衣机滚筒等注塑件。 2、在聚乙烯树脂中的应用 滑石是天然硅酸镁,它独特的微鳞片状结构,具有一定的抗水性和高度的化学惰性,因此有良好的耐化学腐蚀性和滑动性。用它填充聚乙烯可作为工程塑料,有良好的耐化学腐蚀性和流动性,可与ABS、尼龙、聚碳酸脂竞争。用它填充聚乙烯能够提高以下性能:提高韧度、挠曲模量和扭曲模量,提高挠曲强度,降低在常温和高温下下蠕变倾向,提高热变温度及尺寸稳定性,改善变形和翘曲;同时亦有较低的热膨胀系数,改进导热性,提高模塑件的表面硬度及光洁度,提高聚乙烯的机械强度。 添加不同比例的滑石粉对聚乙烯材料的物性将产生不同的影响,添加比例在10-15%达到最佳。对于聚乙烯吹塑薄膜来说,填充超细滑石粉母料比其他填料好,易成型、工艺性好。而且,该种薄膜可使氧气透过率降低80%,特别适合包装含油食品,如花生米、蚕豆等,长期保持不出油、不变质:该种薄膜可使水蒸气透过率降低70%,具有很好的防潮性,很适合作地下土工防潮布,也适用于包装食品。 3、在ABS树脂中的应用 ABS树脂是无定形聚合物,具有聚苯乙烯那样优良的成型加工性;它具有良好的抗冲击强度,耐低温性能好,拉伸强度高耐蠕变性能好。为了提升ABS现有的使用性能,人们对ABS进行改性的研究。 由于ABS是无定型聚合物具有容纳较多填料的功能。其中添加超细滑石粉既能显着地提高ABS原存的性能,又能降低成本。因而多用它注塑成型各种仪表、电视机、收录机、手机等的壳体,当然在其他领域如:纺织器材、电气零件、汽车部件、飞机部件等的应用也非常广泛。 4、在聚苯乙烯树脂中的应用 未改性的通用级聚苯乙烯是无定形聚合物,它硬而脆,但它具有良好的电性能、耐老化性能和高的尺寸稳定性,缺点是脆性高,对环境应力开裂敏感。添加超细滑石粉能够提高冲击韧性,调节流变性,扰曲模量显着提高,抗张屈服强度也有提高。例如:添加40%超细滑石粉或滑石粉母料,扰曲模量从23800kg/cm2增加58800kg/cm2,抗张度从336kg/cm2提高到385kg/cm2。  5、在尼龙树脂中的应用 对尼龙(聚酰胺),在工业上特别注意利用这种塑料的韧性和耐磨性。尼龙一般是硬的,类似角质,具有良好的耐磨性和高的尺寸稳定性。这些性能都可以通过填充剂或增强剂加以进一步提高。在各种填料中,层状结构的滑石粉能提高尼龙原有的好性能,改进耐磨性最为重要。与金属相比未填充改性尼龙弹性模量低,拉伸和蠕变强度低,力学性能与温度有明显的依赖关系,分子上含有吸水基因胺基,吸水率高,制品在使用时易吸水膨胀变形,加工成型时冷却快结晶不完全,在使用时还在结晶,这就导致制品变形,甚至开裂。 尼龙的上述缺点,添加超细滑石粉能够有很大的改善,滑石粉有成核剂的作用,添加后能够提高尼龙的结晶速率,增大结晶度,因此特别能够提高尼龙的韧度、机械强度、硬度、热稳定性、尺寸稳定性,改进制品表面质量和变形行为,对于吸潮性、电性能和化学性能也有好的影响。 6、在聚氯乙烯树脂中的应用 用普通粉体填充聚氯乙烯已经非常普遍地在使用,如制造硬聚氯乙烯管材,填充碳酸钙量可以达到40%,但是聚氯乙烯的抗张强度和冲击强度都要降低;如果添加平均颗粒在5微米即2000目的滑石粉,添加到40-45%体积份数时,可以发现材料的屈服强度甚至高于原来的断裂强度,对聚氯乙烯体系有明显的增强作用。对于冲击强度,添加超细滑石粉,无缺口冲击强度在15%重量份内基本上不降低,缺口冲击强度有所降低,对于扰曲模量,能够显著增加。超细粉体对于添加增韧性剂的聚氯乙烯体系,如PVC/CPE、PVC/ABS体系,则具有十分显着的补强作用。  7、在其他树脂中的应用 1、在含氟聚合物中如聚四氟乙烯,添加滑石粉能够改进蠕变强度、耐磨性、韧度、导热性、压缩强度、硬度、蠕变倾向和在高温下的热变形性。2、在聚甲醛中添加滑石粉填充剂,可以使其本身韧度进一步提高。3、在聚碳酸酯中添加超细目滑石粉,可以提高韧度。4、在聚苯硫醚中添加超细目滑石粉,可以获得较好的加工性,较低的收缩,脱模尺寸精确

07

2019

/

01

Application of water paint on modified vehicles

0引言 与溶剂型涂料相比,水性涂料以水作为溶剂,只以少量醇醚、醇酯等作为成膜助剂,能够大幅度降低VOC(挥发性有机物)排放量。如水性底色漆的有机溶剂含量为5%~15%,而溶剂型底色漆的有机溶剂含量为80%左右,使用水性底色漆替代溶剂型底色漆,可使VOC排放量从45g/m2降至7g/m2。随着人们环保意识的增强和国家对清洁生产的要求,并且经过水性涂料的不断升级,在某些性能和价格上水性涂料与溶剂型涂料已基本相当,油转水已成为民心所向,大势所趋。但是由于水性涂料的施工条件及施工工艺的限制,水性涂料的进展,与发达国家相比,仍存在较大差距[1]。本文就水性涂料的特点,根据成功应用案例,浅谈下水性涂料在改装车领域的应用及工艺。 1改装车水漆应用现状目前,我国的改装车(包含消防车、油罐车、水泥搅拌车、自卸车、救援车等特种车辆和洒水车、垃圾清理车、清扫车等环卫车辆在内)生产市场发展突飞猛进,改装车市场受益于国民经济的发展和公路基础设施的建设带来的货物运输量的增长,行业范围和市场空间都在不断扩大,每年都有百万辆的量产。而改装车涂料多采用溶剂型喷(或浸)漆,而溶剂型涂料中含有溶剂,在生产和运输过程中排放大量的VOC,危害人类健康,造成环境污染。车辆用涂装材料正向着高固体分、水性化和粉末化方向发展。虽然国内市场已经针对改装车涂料做了水性化的研究,并且已成功在改装车辆、农机车辆、等领域进行水性化的涂装[2]。但是仍没有广泛使用,除价格因素外,主要原因在于缺少全套的解决方案,不能满足不同零部件的不同性能及施工要求。目前国内用于改装车的水性涂料还不足5%,一般选用进口的水性漆,而国内生产的水性改装车用漆性能与国际先进水平仍有一定差异[3]。 2 改装车用水性漆特点及施工工艺注意事项虽然水性涂料更具有环保性,但是由于水性涂料的特性,往往限制了它的性能和应用[4],例如:水的热熔大,更加难于挥发,在高湿度条件下容易使漆膜产生流挂现象;水的表面张力较大,润湿性较差,不对涂料加以调整会影响到漆膜成品的表面质量;水的粘度受剪切力影响变化很大,在受到高剪切作用时,水性涂料的粘度会下降很多,会对输调漆系统带来很大影响;水对金属材料有较大的腐蚀性,会对与之接触的涂装设备造成腐蚀。正因为水与溶剂存在上述不同的特性从而导致了水性涂料和溶剂型涂料在诸多方面的差异性,也导致了,水性漆与油性漆施工方式和性能的差异。因此,在施工过程中特别需要注意以下几个方面[5]:a底材要处理干净,无油无浮尘。b水漆配比要准确,按重量比准确称量加入,严格控制施工粘度。c配漆固化剂要先和漆充分搅匀,再加水稀释,过滤后使用。d极端环境下,如高温,低温,高湿状况下,使用时要外加一些专门的助剂。e喷涂边角和有棱台的地方需特别注意,防止喷涂过厚流挂,避免起痱子。f底漆最少自然干燥4小时后再喷涂面漆,以确保面漆的最佳效果。面漆表干后可进行喷字作业,6小时后贴反光胶带。  3改装车水漆设备改造  目前,水性涂料与溶剂型涂料生产线基本相似,现有油性涂装设备上不需进行大的改造就可使用水性涂料进行涂装。根据水性涂料的特性,溶剂型涂料的涂装生产线需要对某些设备及工艺进行改造和调整[6]。a水性漆的表干快,但实干相对较慢,且快速烘干易产生气泡,一般要求流平时间不小于15分钟,低温烘干工件表面温度要求不小于60℃,时间不少于25分钟;b水性漆以水为分散介质,易引起普通的碳钢锈蚀,一般喷涂设备与供漆设备为不锈钢或PVC材质;并对喷涂现场的碳钢件做好防护,避免产生锈蚀;c水性漆的干燥性能与环境中的温湿度相关,温度高,湿度低,漆膜则干燥快;温底低,湿度高,漆膜干燥慢,易流坠或流挂,过厚的漆膜易产生气泡;喷涂室、流平室、烘干室要进行空气温湿度的控制,要求温度≥10℃,湿度≤75%;d水性漆粘稠度与油性漆不同,一般喷涂粘度较高,粘稠度低易产生流坠或流挂,则要求喷涂设备压力,采用空气喷涂,压缩空气压力为0.6-0.8MPa,也可采用混气喷涂设备,或采用高压无气喷涂设备,对于结构大的工件,为提高喷涂的效率,空气喷涂或混气喷涂的喷枪口径采用1.8以上。 4水性涂料在改装车涂装中的应用由于改装车辆主要在户外作业,身处风吹日晒、高湿热、温差大、路况差的环境,所以对涂层的装饰及防护性能要求较高。从国内外改装车行业水性涂料的使用状况来看,水性配套体系用漆主要是双组份环氧底漆、双组份环氧中间漆、双组份丙聚中间漆、双组份丙烯酸聚氨酯面漆。目前我公司经过不断努力开发的水漆级配套体系:环氧底漆+聚氨酯面漆、环氧底漆+中涂漆(丙聚、环氧)+聚氨酯面漆,已达到了在改装车上应用的要求。并且已成功应用于:深圳东风汽车、三一重工、山东临工、中机美诺、山东建宇、时风集团等用户。配套产品特性:对水分、空气及腐蚀物的渗透性小;与被涂装材料吸附力强,持久耐磨;对金属有很好的防锈、到点、绝缘及隔热等性能,并有较好的外观展示效果;针对不同基材、不同部位的不同技术要求设计全套涂装方案及流程;在低温及常温下快速干燥的特性;满足各种大批量及小批量生产的设备及零部件的涂装;不含卤代烃、苯、甲苯、二甲苯等有害物质,重金属含量低,解决了溶剂型油漆VOC含量高,污染严重及火灾隐患的问题,有效简化及降低了企业通风,水处理等方面的流程及成本等,还有助于降低职业病发生的潜在机率,产品施工方便、应用面广、适合大规模工业化连续生产。

07

2019

/

01

Teach you how to identify counterfeit titanium dioxide?

Introduction of titanium dioxide titanium dioxide chemical name: titanium dioxide, molecular formula TiO2, molecular weight 79.9, its mass composition of 59.95% for Ti,O 40.05%. Alias: titanium dioxide, titanium dioxide. Usually, people call titanium dioxide, which is mainly used for white pigments in industries such as coatings, inks, plastics, rubber, papermaking, chemical fiber, art pigments and daily cosmetics, as titanium dioxide, titanium dioxide pigment or titanium dioxide, while titanium dioxide, which is mainly used for purity in enamel, welding rod, ceramics, electronics, metallurgy and other industrial sectors, is called titanium dioxide or non-pigment grade titanium dioxide and non-coating titanium dioxide. Rutile titanium dioxide, and there are two kinds of manufacturing methods, different manufacturing methods, the quality is different. Sulfuric acid method manufacturing: large particle size, red color. The hue is not very white, gray or yellow, and the hue is different from batch to batch. Therefore, it cannot be used in high-end buildings. Chlorination method manufacturing: fine particle size, color blue light. Hue pure white, very stable. Technical indicators of titanium dioxide: TiO2 said whiteness, hiding power (opacity, coloring strength), the higher the percentage content, the greater the whiteness and hiding power. Al2O3 means dispersion, gloss, weather resistance (treated with dense aluminum), the higher the percentage content, the greater the dispersion and gloss. SiO2 represents weather resistance (treated with dense silicon), and the higher the percentage content, the greater the weather resistance. The organic substance is coated with the organic substance, and the dispersibility (wetting) is better. ColorL represents whiteness (brightness). The average particle size determines light scattering and hiding properties. The smaller the particle size, the more the color of titanium dioxide is blue phase. Oil absorption affects the gloss and dispersion of the system. The resistance value indicates the soluble salt content. Basic requirements for rutile titanium dioxide powder: TiO2 content,%(m/m)≥ 97(R1), 90(R2), 80(R3); Volatiles at 105 ℃,%(m/m)≤:0.5(R1),R2, ≤ agreed; Water soluble,%(m/m): 0.6(R1), 0.5(R2), 0.7(R3); residue on sieve (45 μm mesh,%(m/m)≤ 0.1). Basic requirements for rutile titanium dioxide: the agreed reference sample shall meet the basic requirements. Color: similar to the agreed reference sample; Volatile scattering force (instead of achromatic force): agreed; After pretreatment at 23±2 ℃ and relative humidity (50±5)% for 24h, 105,%(m/m)≤:0.5(R1), 1.5(R2), (R3); PH value of water suspension 2.5, oil absorption and resistivity of water extract are all agreed. Due to the relatively high price and large dosage of rutile titanium dioxide, there are many counterfeit products on the market, mainly including the following aspects: (1) packaging domestic titanium dioxide into imported titanium dioxide (2) using anatase titanium dioxide as rutile type or mixing part of anatase titanium dioxide into rutile type; (3) mixing rutile titanium dioxide or titanium calcium carbonate and other filling materials such as anatase titanium dioxide or barium sulfate. Prevention and identification of counterfeit products: (1) imported titanium dioxide usually has its characteristics on its packaging (such as patterns, fonts, batch numbers, etc.), which can be identified on its packaging first; (2) for anatase titanium dioxide posing as rutile titanium dioxide, it is difficult to distinguish with general chemical methods, and can only be identified by X-diffraction. (3) For CaCO3 mixed in titanium dioxide, it can be identified by adding dilute sulfuric acid or dilute hydrochloric acid into titanium dioxide, which will produce bubbles and make clear lime water turbid, indicating that CaCO3 is mixed in titanium dioxide; (4) For those mixed with lithopone in titanium dioxide, adding dilute sulfuric acid or dilute hydrochloric acid will produce the smell of rotten eggs; (5) For those mixed with BaSO4, because it cannot react with acid, it can only be identified by X-diffraction.

07

2019

/

01

< 1 >