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1.
研究了聚丙烯(PP)/膨胀型阻燃剂(IFR)体系所使用协效剂的协效作用。极限氧指数(LOI)与垂直燃烧(UL 94)测试结果表明:将各种协效剂加入到PP/IFR中,均能在一定程度上提高其阻燃性能;通过热重分析(TGA)测试,将协效剂按作用机理分为3类:与聚磷酸铵(APP)和季戊四醇(PER)均不发生化学反应的协效剂;仅与APP反应而不与PER反应的协效剂;与APP,PER都发生化学反应的协效剂。并通过电子扫描显微镜(SEM)和炭层强度测试对燃烧后所形成的炭层进行表征,结果表明虽然协效剂作用机理不同,但本质上都对炭层具有一定的增强作用,使炭层附着于基体表面,阻隔热量与氧气进入到燃烧区域,从而达到阻燃目的。  相似文献   

2.
以双酚A型环氧树脂为基体、甲基纳迪克酸酐为固化剂、聚磷酸铵为膨胀阻燃剂、水热法制备的二氧化钛纳米管(TNTs)为阻燃协效剂,共混后交联固化制得了膨胀阻燃型环氧树脂复合材料。采用极限氧指数测试、垂直燃烧实验、扫描电镜和拉曼光谱分析了添加TNTs对环氧树脂膨胀阻燃材料的阻燃成炭协效作用。结果表明:TNTs的引入提高了环氧树脂膨胀阻燃材料的极限氧指数以及垂直燃烧UL-94测试评级。当TNTs质量分数为2%时,膨胀阻燃体系的极限氧指数达到28.4%,UL-94达到V-1级。同时,TNTs延缓了环氧树脂膨胀阻燃材料在高温下的热降解,提升了体系高温热稳定性和成炭性能。TNTs可以作为成炭的网络骨架,并促进高温下生成更多连续致密的炭层结构,且高温煅烧后残留的炭层具有更低的ID/IG(拉曼光谱在1 360 cm-1及1 600 cm-1处的吸收峰强度比)值,石墨化程度更高,炭层结构更加致密规整。  相似文献   

3.
以聚磷酸蜜胺(MPP)/季戊四醇(PER)/聚磷酸铵(APP)三元膨胀型阻燃剂(IFR)(其中P/PER/三聚氰胺(MA)的摩尔比为4.1/1.0/1.1)对聚酰胺6(PA6)/有机蒙脱土(OMMT)纳米复合材料(wOMMT=0.03)进行阻燃,测定了阻燃PA6/OMMT的极限氧指数(LOI)及垂直燃烧阻燃性(UL94),以锥形量热仪(CONE)测定了材料诸多与火灾安全性有关的阻燃参数,包括释热速率、有效燃烧热、总释热量、质量损失速率、比消光面积及引燃时间等,并与PA6、阻燃PA6及PA6/OMMT进行了比较,用扫描电镜(SEM)观察了由CONE测试所得残炭的形态。  相似文献   

4.
将叶蜡石(PYR)与膨胀型阻燃剂[IFR,聚磷酸铵(APP)/季戊四醇(PER)/三聚氰胺(Mel))复配],应用于不饱和聚酯树脂(UPR),得到膨胀型阻燃UPR复合材料。通过氧指数(LOI)、垂直燃烧(UL94)、烟密度等级(SDR)、热分析(DSC-TG)对阻燃复合材料的阻燃、抑烟及热稳定性能进行了研究。结果表明:在该膨胀型复配阻燃体系中,叶蜡石与IFR存在明显的协效作用,在mPYR∶mAPP∶mPER∶mMel=4∶2∶1∶1,复合阻燃剂的含量为40%的情况下,LOI高达36.4,阻燃级别为UL94 V-0级,SDR为62.95,满足国家对B1级电器类热固性塑料的使用要求。  相似文献   

5.
使用以乙烯/醋酸乙烯共聚物(EVA)为相容剂的高密度聚乙烯/蒙脱土(HDPE/OMT)纳米复合材料作为基体,制备了含不同成炭剂的聚磷酸铵(APP)膨胀阻燃体系,对其阻燃性能进行了比较和研究,并分析了蒙脱土与膨胀阻燃剂协效作用的机理。热重分析(TGA)、垂直燃烧(UL-94)、极限氧指数(LOI)、锥形量热计结果表明:APP/季戊四醇(PER)体系熔融过程较短可形成蒙脱土增强炭层;PER/PA/OMT体系中较高的有机物含量有利于蒙脱土迁移和堆积。  相似文献   

6.
碱式硫酸镁晶须阻燃乙烯-醋酸乙烯酯共聚物的研究   总被引:1,自引:0,他引:1  
利用极限氧指数、UL-94垂直燃烧试验、锥形量热器、拉伸测试等手段研究了碱式硫酸镁晶须(MOS)填充阻燃乙烯-醋酸乙烯酯共聚物(EVA)的燃烧性能和力学性能,并与氢氧化镁(MH)填充阻燃EVA进行了比较。实验结果表明:MOS是一种性能优良的无卤阻燃剂。当填充量相等时,与EVA/MH相比,EVA/MOS具有更高的极限氧指数和UL-94垂直燃烧级别,更低的热释放速率、有效燃烧热和质量损失速率,以及更高的力学强度。  相似文献   

7.
将三聚氰胺氰尿酸盐(MCA)阻燃剂添加到玻纤增强的尼龙66复合材料(GF-PA66)中。利用UL-94实验对MCA在复合材料中的阻燃效果进行研究;通过扫描电子显微镜(SEM)分析了燃烧后的样品形貌,并利用热重分析法对复合材料的热分解行为进行了研究。结果表明:MCA可使玻纤增强尼龙66复合材料达到UL-94 V-0级阻燃效果;MCA晶体被均匀地分散于尼龙基体中,在燃烧时MCA通过自身吸热分解,产生不可燃气体,实现气相阻隔,从而起到阻燃作用,并在复合材料自熄面上留下纳米级气孔。  相似文献   

8.
首先以4,4-联苯二甲醚(BMBP)和2,6-二甲基苯酚为单体、对甲苯磺酸(PTS)为催化剂,合成了联苯基酚单体(BDBP)。将BDBP进行氰化后,成功制备了一种新型联苯基二元氰酸酯(BDBPCy)。利用红外光谱(FT-IR)和质谱(MS)对酚中间体及氰酸酯单体结构进行了表征。通过差示扫描量热法(DSC)、动态热机械分析(DMA)等测试手段考察了固化后树脂的热性能、力学性能、介电性能、耐湿热性及阻燃性能。结果表明:BDBPCy树脂结构中引入的联苯结构,使得树脂在固化后具有良好的热稳定性及自阻燃性能,800 °C的质量残留率为42%,玻璃化转变温度为258 °C,UL-94垂直燃烧实验测试结果为V-0级别。同时,结构中的大体积联苯基团和邻位甲基基团进一步提高了树脂的介电性能和耐湿热性能。  相似文献   

9.
通过原位聚合法,以密胺树脂(MF)为壁材,制备了微胶囊包覆聚磷酸铵(MCAPP),然后密炼将MCAPP与聚乳酸(PLA)熔融共混,得到微胶囊包覆聚磷酸铵阻燃聚乳酸,并研究了不同树脂包覆率的MCAPP对共混物形貌结构、加工性能、热性能、力学性能以及阻燃性能的影响。结果表明,在原位聚合过程中,当MF质量分数为17.2%时,MCAPP树脂包覆率可达13.2%,共混物中PLA结晶度提高,降解程度最低,同时阻燃效果最佳,极限氧指数可达39.4%,并且垂直燃烧等级达到UL94 V0级。  相似文献   

10.
以聚醚(N210)、异佛尔酮二异氰酸酯(IPDI)为基本单体,[(双(2羟乙基)氨基)甲基]磷酸二乙酯(FRC6)、一缩二乙二醇(EX)为扩链剂,二羟甲基丙酸(DMPA)为亲水扩链剂, 3(2氨乙基)氨丙基甲基二甲氧基硅烷(KH602)为后扩链剂,合成了一系列有机磷(P)阻燃改性的水性聚氨酯乳液。研究表明:随着FRC6用量的增加,聚氨酯(PU)的起始热分解温度降低,但热释放速率也降低,而PU的阻燃性能得到很大的提高。当FRC6中P的含量占预聚体的质量分数为2.31%时,其氧指数为28%,垂直燃烧测试显示PU的阻燃性能已达到UL94V2级。  相似文献   

11.
CASE HISTORY A female patient, 46 years old, head of the foreign affairs department of a certain university in Beijing, paid her first visit on October 9, 2006, with the chief complaint of vomiting for one month. She got vomiting after meals in early September. Before that, she had discomfortable sensation in the stomach due to angry with others, but she didn't pay much attention. Later, it developed into vomiting after eating. After the vomiting, the discomfort would be relieved, but with slight hypodynamia. She was once diagnosed as having 'neurogenic vomiting'. Having taken some western and Chinese drugs, the above symptoms were a little bit improved, but she would have nausea upon eating and with regurgitation. Because of the fear for vomiting, she did not dare to have food intake, with body weight reduction of 6 kilos in one month.  相似文献   

12.
Radiotherapy and chemotherapy are the important modern medical therapies for malignant tumors,yet they can also bring about serious local and systemic toxic side reactions so to decrease the patient;'s life quality,manifested by a series of consumptive symptoms.Having engaged in the combined work of Chinese and western medicine for nearly 50 years,the research fellow Qiu Baoguo in Henan Provincial Academy of TCM has developed his unique views on the TCM study of consumptive syndromes.The author of this essay had once the fortune tO follow Dr.Qiu in clinic,and specially would like to introduce in the following Dr.Qiu's experience in treating consumptive syndromes after radio-chemotherapies for patients with malignant tumor.  相似文献   

13.
OBJECTIVE: To observe therapeutic effects of the comprehensive therapy of acupuncture-moxibustion and Chinese Tuina for treatment of insomnia due to deficiency of both the heart and spleen. METHODS: 92 cases were divided randomly into the treatment group (treated by acupuncture-moxibustion and Chinese Tuina) and the control group (treated by acupuncture-moxibustion). RESULTS: The therapeutic effect of the treatment group was obviously superior to that of the control group (the CHI2 test showed P < 0.01). CONCLUSIONS: The comprehensive therapy of acupuncture-moxibustion and Chinese Tuina can give marked therapeutic effects for treatment of insomnia due to deficiency of both the heart and spleen.  相似文献   

14.
15.
Objective: To investigate if there are the CK-19, PDX-1, Nestin, Ngn3 positive cells in the donor islets of different purity in rats. Methods: Thirty male adult SD rats were randomly divided into 3 groups. Islets were isolated using digestion by ductal injection of collagenase. Group Ⅰ (n=10): Separating cell preparations were not purified, Group Ⅱ(n=10): Islet sediment was purified with 25% Ficoll400 ,Group Ⅲ (n=10): Islet sediment was purified with 25% and 11% Ficoll-400. The levels of protein of CK-19, PDX-1, Nestin and Ngn3 were detected by immunohistochemistry and the mRNA of CK-19, PDX-1, Nestin, Ngn3 was amplified by RT-PCR. Results: After two different purification methods applied, three islet preparations of different purities were obtained. The difference of islet purity was significant among various groups (P<0.05). Compared with group Ⅱ and group Ⅲ,the protein and mRNA of CK-19, PDX-1, Nestin,Ngn3 were both higher in group Ⅰ; group Ⅲ was poorly expressed. Conclusions: The three different islet purity donor islet have different CK-19, PDX-1, Nestin, Ngn3 positive cells within them, indicating that there are some islet stem cells in the purified donor islet.  相似文献   

16.
Objective:To investigate the optimum screening conditions of associated proteins in human psoriasis vulgaris by serum proteomics technique, and to screen the different expression proteins related with psoriasis vulgaris. Methods:Serum samples of peripheral blood were collected from newly diagnosed psoriasis vulgaris patients in the clinic, and 20 matched healthy persons. Serum albumin IgG was removed by filtering with ProteoExtract Albumin/IgG. After comparative proteomics analysis the different protein spots were identified using 2-DE and MS. Results :Electrophoresis figures with high resolution and reproducibility were obtained. Three different expression proteins were found only in the serum from psoriasis vulgaris patients, while nine other different proteins expressing from healthy volunteers. Conclusion:The protein expression was different in the serum between the psoriasis vulgaris patients and healthy volunteers. It was hoped that we could find the biomarkers related to psoriasis vulgaris by using proteomics.  相似文献   

17.
PYTOBEZOARS are common bezoars in gastrontestinal tract, commonly seen in stomach and mall intestine,1but huge disopyrobezoars are  相似文献   

18.
CASE HISTORY A male,a retired officer of 61 years old,paid his first visit on May 12,2006.The patient stated that 2 weeks before he suddenly got paroxysmal precordial choking pain,with irregular attacks.Each attack would last several seconds to several minutes.The attack was accompanied with heavy oppressed sensation in the precordial region,palpitation,lassitude,and in severe cases,sweating,which was once diagnosed by a hospital as'coronary heart disease'.Recalling the case history,the patient said that several days before he got angry with others because of some affairs in work,and he was not so used to the life pattern since he had just retired from his busy working post.At usual times,he was quick tempered and peevish.In recent days,he had poor appetite,and loose stool.  相似文献   

19.
The English edition of Chinese Journal of Integrative Medicine is edited and published by the Chinese Journal of Integrated Traditional and Western Medicine Press.Original scientific papers of advanced clinical and experimental medicine in the field of complementary/alternative medicine or integrative medicine are expected.  相似文献   

20.
<正>As culture is the soul of a nation,the three books,"History of Chinese Philosophy,""History of Chinese Culture"and"History of Chinese Science and Technology"have demonstrated the superiority of our great Chinese culture,and its significant impact in the field of international culture.Both core value and practical value of the Chinese culture are very clear,reflected in the views of universe,nature,life,health,disease,and therapy and related considerations,concepts,and technical methods.  相似文献   

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