阻燃劑其按元素種類分為:鹵係、磷係、鹵-磷係、氮係、矽係、鋁鎂係等,按化學結構分為無機阻燃劑、有機阻燃劑、高分子阻燃劑等,按阻燃劑與被阻燃材料關係分為添加型阻燃劑和反應型阻燃劑。
通常在塑料阻燃改性中常采用的方法是添加型阻燃劑共混改性。PP(聚丙烯)阻燃常采用的阻燃劑包括:鋁鎂係阻燃劑,即氫氧化鎂、氫氧化鋁;磷係阻燃劑,紅磷母粒等;氮係阻燃劑MCA、MA等;有些還采用有機矽阻燃劑。
聚(ju)丙(bing)烯(xi)質(zhi)地(di)發(fa)脆(cui),抗(kang)衝(chong)擊(ji)性(xing)能(neng)較(jiao)差(cha),如(ru)果(guo)在(zai)聚(ju)丙(bing)烯(xi)中(zhong)引(yin)入(ru)相(xiang)溶(rong)性(xing)差(cha)或(huo)親(qin)和(he)力(li)差(cha)的(de)無(wu)機(ji)材(cai)料(liao),客(ke)觀(guan)上(shang)起(qi)到(dao)了(le)填(tian)充(chong)作(zuo)用(yong),往(wang)往(wang)會(hui)使(shi)聚(ju)丙(bing)烯(xi)的(de)機(ji)械(xie)性(xing)能(neng)更(geng)加(jia)惡(e)化(hua),拉(la)伸(shen)強(qiang)度(du)、chongjiqiangdukenenghuiyuanyuanbunengmanzuzhibiao,muqiangaishandefangfachangcaiyongzengrenjizengren,zengrenjijiagegao,zengrendetongshicailiaodegangxingyoubiancha,henkenengshiqushiyongjubingxiyuanbenjiazhi。suoyiduiyujubingxizuihaobucaiyongwujitianchongfangshigaixinghuojiangdichengben,zaichongfenliyongqizishentediantongshishidanggaijinxingnengzhibiaoweishangce。
做阻燃聚丙烯通常采用的阻燃劑有鹵係(一般為溴係);無機的氫氧化鎂、氫氧化鋁;磷係,紅磷等;氮係MCA、MA等及有機矽係。
qingyanghuameidengshuyuwujizuranji,zuranjilishiranshaoshishifangchujiehedeshui,tongshigaotianchongliangyejiangdileyoujicailiaodekeranxing。yongqingyanghuameidengzuranyoudianshihuanbaoxinghao,bushifangyanwu,buchanshengyouhaiheyouzhengyideqiti,chengbendilian。quedianshitianjialiangdaqieqinhelicha,V0阻燃級別一般添加比例≥65%,這樣高的添加量可以認為阻燃的PP中無機填料占到整個體係的2/5以上。直接導致的後果是阻燃PP比重大,超過1.5;拉伸強度由普通未阻燃PP的23左右下降到18以下;伸長率由23左右下降到1.3;衝擊強度由15下降到1左右。嚴重惡化了PP的性能。所以往往被采用在軟化點要求高而其它性能可以忽略的場合。
磷係阻燃劑多為液體,閃點低,高溫可能釋放有毒氣體,在聚丙烯中應用不多。固體的紅磷也是PP阻燃常采用的阻燃劑,相比氫氧化鎂等阻燃劑的高填充紅磷阻燃劑有明顯優勢。其一般添加比例在8%-12%可以做到離火自熄,經過包覆處理的紅磷吸潮性和易燃性大為改觀。可以經受300℃yixiadewendu,zaijiagongguochengzhongyibanbuyishihuo。yonghonglinzurangengjiashiyongyuheisehuohongsezhipin,qitayansehennanduihongsexingchengzhedang。honglindelingwaiquedianjiushizurandecailiaoyangzhishubijiaodi,xiangrongxingbugouhao,liudongxingcha。shiheduizhipinwaiguan、性能等要求不高的場合使用。
溴類阻燃劑是鹵係阻燃劑中的“代表作”,由(you)於(yu)溴(xiu)分(fen)子(zi)大(da)於(yu)氯(lv)分(fen)子(zi),且(qie)鍵(jian)能(neng)小(xiao),阻(zu)燃(ran)效(xiao)率(lv)高(gao)。所(suo)以(yi)現(xian)在(zai)鹵(lu)係(xi)阻(zu)燃(ran)劑(ji)多(duo)采(cai)用(yong)溴(xiu)類(lei)。人(ren)們(men)對(dui)鹵(lu)素(su)阻(zu)燃(ran)劑(ji)研(yan)究(jiu)比(bi)較(jiao)深(shen)入(ru),透(tou)徹(che)。原(yuan)因(yin)是(shi)其(qi)阻(zu)燃(ran)效(xiao)果(guo)好(hao),效(xiao)率(lv)高(gao),使(shi)用(yong)方(fang)便(bian),與(yu)樹(shu)脂(zhi)相(xiang)溶(rong)性(xing)最(zui)好(hao)且(qie)便(bian)於(yu)加(jia)工(gong),用(yong)其(qi)阻(zu)燃(ran)的(de)製(zhi)品(pin)力(li)學(xue)性(xing)能(neng)好(hao),且(qie)性(xing)價(jia)比(bi)高(gao),技(ji)術(shu)成(cheng)熟(shu)。常(chang)用(yong)於(yu)PP阻燃的鹵係阻燃劑包括包括十溴二苯醚,四溴雙酚A,八溴醚,十溴二苯乙烷,四溴醚,溴代聚苯乙烯,六溴環十二烷及氯化石蠟,得克隆,CPE等。其各自有其阻燃特點,十溴二苯醚是塑料阻燃劑的“老大哥”。其技術成熟,產量高,價格低,通用性強。在PP阻(zu)燃(ran)中(zhong)也(ye)常(chang)常(chang)采(cai)用(yong)。目(mu)前(qian)麵(mian)臨(lin)的(de)問(wen)題(ti)是(shi)歐(ou)盟(meng)的(de)非(fei)議(yi)使(shi)其(qi)為(wei)原(yuan)料(liao)的(de)產(chan)品(pin)出(chu)口(kou)受(shou)到(dao)很(hen)大(da)限(xian)製(zhi)。十(shi)溴(xiu)二(er)苯(ben)乙(yi)烷(wan)是(shi)其(qi)升(sheng)級(ji)品(pin)種(zhong),環(huan)保(bao)性(xing)能(neng)好(hao),公(gong)認(ren)不(bu)含(han)多(duo)溴(xiu)聯(lian)苯(ben)、多溴聯苯醚,阻燃性能與十溴二苯醚幾乎相當,主要是為了應對歐盟的RoHS指令,但是目前使用成本相對也要提高。八溴醚是阻燃PP最常用的阻燃劑,其主要特點是阻燃PP效xiao率lv高gao,相xiang對dui十shi溴xiu二er苯ben醚mi等deng達da到dao相xiang同tong阻zu燃ran等deng級ji其qi用yong量liang小xiao很hen多duo,使shi用yong成cheng本ben較jiao為wei經jing濟ji,但dan是shi八ba溴xiu醚mi的de致zhi命ming缺que點dian是shi不bu耐nai遷qian移yi,容rong易yi起qi霜shuang,所suo以yi用yong其qi阻zu燃ran的dePPjingchangchuxianbiaomianmaoshuangxianxiang。youqiyongyudaiyansedezhipinnanyirenshou。lingwaibaxiumizaigongjujubingxihegongchengjubingxizhongzuranxiaolvdadajiangdi,wangwangxiaoguobuhenlixiang。qitaleiluxizuranjizaibukaolvchengbendeqingkuangxiadoukeyiyongyujubingxi。qizailixuexingnenghejiagongshiyidufangmiangeyouyoulie。
溴xiu係xi阻zu燃ran劑ji阻zu燃ran聚ju丙bing烯xi遇yu到dao的de最zui大da問wen題ti體ti現xian在zai環huan保bao性xing能neng,製zhi品pin的de機ji械xie性xing能neng和he使shi用yong成cheng本ben等deng方fang麵mian。環huan保bao問wen題ti是shi溴xiu係xi阻zu燃ran劑ji討tao論lun最zui多duo的de話hua題ti,自zi從congRoHS指zhi令ling頒ban布bu並bing實shi施shi,環huan保bao性xing就jiu成cheng為wei溴xiu係xi阻zu燃ran劑ji經jing常chang爭zheng論lun的de話hua題ti,對dui於yu出chu口kou型xing企qi業ye來lai說shuo麵mian臨lin成cheng本ben增zeng加jia,利li潤run降jiang低di,市shi場chang萎wei縮suo的de考kao驗yan。八ba溴xiu二er苯ben醚mi和he六liu溴xiu苯ben已yi經jing成cheng為wei公gong認ren的de“天敵”,產生“二惡英”yijingchengweigongren,muqianjihushichangnanyijiandao,shixiuerbenmizaibeishouzhengyizhihoubeifangzailehuomianlingli,suiranoumengtongyile,danqishichangqianjingburongleguan,bijingjinglile“談溴色變”的時代。一朝被蛇咬,十年怕井繩嘛。取而代之十溴二苯乙烷,因為目前還沒有發現其燃燒時產生“二惡英”。十shi溴xiu二er苯ben乙yi烷wan目mu前qian在zai國guo內nei已yi經jing有you多duo家jia工gong廠chang在zai生sheng產chan,價jia格ge下xia降jiang不bu少shao。其qi應ying用yong與yu十shi溴xiu二er苯ben醚mi近jin乎hu相xiang同tong,理li論lun上shang其qi耐nai遷qian移yi性xing要yao好hao於yu十shi溴xiu二er苯ben醚mi,實shi際ji結jie果guo往wang往wang低di於yu預yu期qi值zhi。使shi用yong十shi溴xiu二er苯ben乙yi烷wan阻zu燃ran聚ju丙bing烯xiV2級以上,阻燃劑與協效劑總量一般要超過總體係的12%,阻燃效率不是很理想。
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