CN110183796B - 一种低成本废料回收pvc木塑板材 - Google Patents
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Abstract
本发明公开了一种低成本废料回收PVC木塑板材,它是由下述重量份的原料组成的:废旧PVC料130‑200、酯改性木粉30‑40、硬脂酸钙4‑6、壬二酸二辛酯5‑7、聚四氟乙烯粉3‑4、ac发泡剂10‑15,本发明的木塑材料采用聚四氟乙烯粉对木塑板材进行增韧改性,而有机化后的木粉则可以在有机基体间良好的分散,进而提高了成品板材的综合性能。
Description
技术领域
本发明属于PVC材料领域,具体涉及一种低成本废料回收PVC木塑板材。
背景技术
木塑复合材料是利用木粉、竹粉、果壳粉或农作物秸秆粉和塑料树脂或废旧塑料为主要原料,经高温混合、成型加工而制得的一种新型环保复合材料。木塑复合材料比原木材料有更好的耐老化性能、耐吸水性和耐翘曲性能,同时可以防虫蛀、抗腐蚀,无须防腐理进而减少环境污染,且成本比纯木材或塑料低40-60%,可以被加工成各种空心型材,因此木塑复合材料被广泛应用于许多领域,是最具潜力的一种新型材料。
目前一般选用聚氯乙烯、聚烯烃、聚苯乙烯等树脂作为木塑复合材料的基体,其中以PVC为基体的木塑复合材料是国内外学者进行发泡研究的重点,但由于PVC树脂加工时需要添加多种助剂,发泡有一定困难,加入植物纤维成分后,树脂熔体粘度、制品刚度等都有增加,也进一步增加了PVC植物纤维复合材料的发泡难度。同时PVC木塑复合板材中的PVC树脂分子链结构中有大量的极性C-Cl键,分子之间存在较大的作用力,因此相对于其他通用树脂,PVC属于硬脆材料,冲击强度较低,且具有缺口敏感性,受外力冲击时易脆裂,难以用作结构材料。这些缺点极大地限制了PVC在高性能领域的发展,为扩大其应用范围,需要对硬质PVC进行增韧改性。
发明内容
本发明的目的在于针对现有技术的缺陷和不足,提供一种低成本废料回收PVC木塑板材。
为实现上述目的,本发明采用以下技术方案:
一种低成本废料回收PVC木塑板材,它是由下述重量份的原料组成的:
废旧PVC料130-200、酯改性木粉30-40、硬脂酸钙4-6、壬二酸二辛酯5-7、聚四氟乙烯粉3-4、ac发泡剂10-15。
所述酯改性木粉是由下述重量份的原料组成的:
秸秆粉10-20、废旧木粉40-50、γ-(2,3-环氧丙氧)丙基三甲氧基硅烷10-13、催化剂0.01-0.02、丙烯酸6-9、松香3-4、8-羟基喹啉1-2、四丁基溴化铵0.04-0.05。
所述的催化剂为浓度为96-98%的盐酸水溶液。
所述酯改性木粉的制备方法,包括以下步骤:
(1)取γ-(2,3-环氧丙氧)丙基三甲氧基硅烷,加入到其重量20-30倍、35-40%的甲醇水溶液中,搅拌均匀,得硅烷溶液;
(2)取秸秆粉、废旧木粉混合,加入到浓度为0.7-1mol/l的氢氧化钠溶液中,浸泡2-3小时,出料,常温干燥,得预处理粉料;
(3)取上述预处理粉料,加入到硅烷溶液中,超声1-2小时,加入催化剂,在60-70℃下保温搅拌5-7小时,出料冷却,得改性分散液;
(4)取松香,加入到其重量15-20倍的无水乙醇中,送入到55-60℃的恒温水浴中,搅拌溶解,加入8-羟基喹啉,搅拌均匀,出料,与上述改性分散液混合,搅拌均匀,加入丙烯酸,送入到反应釜中,加入四丁基溴化铵,调节反应釜温度为115-120℃,保温搅拌2-3小时,出料冷却,旋蒸,除去溶剂,即得所述酯改性木粉。
所述板材的制备方法,包括以下步骤:
将废旧PVC料经过分选后干燥,磨粉,与硬脂酸钙混合,在100-120℃下预热20-30分钟,加入聚四氟乙烯粉、发泡剂、酯改性木粉搅拌均匀,送入到挤出机中,熔融挤出,冷却,即得。
本发明的优点:
本发明首先以秸秆粉、废旧木粉为原料,采用γ-(2,3-环氧丙氧)丙基三甲氧基硅烷处理,然后以盐酸为催化剂,制备poss改性的分散液,然后将松香分散到醇溶液中作为溶剂,将poss改性的分散液于丙烯酸共混反应,得到酯化改性的木粉,通过该反应,有效的改善了木粉在废旧PVC料间的分散性能,提高了成品材料的力学稳定性强度,本发明的木塑材料采用聚四氟乙烯粉对木塑板材进行增韧改性,而有机化后的木粉则可以在有机基体间良好的分散,进而提高了成品板材的综合性能,本发明的采用以废旧PVC料为基料,经过分选后重复利用,有效的降低了生产成本,且成品质量较好,综合性能优越。
具体实施方式
实施例1
一种低成本废料回收PVC木塑板材,它是由下述重量份的原料组成的:
废旧PVC料130、酯改性木粉30、硬脂酸钙4、壬二酸二辛酯5、聚四氟乙烯粉3、ac发泡剂10。
所述酯改性木粉是由下述重量份的原料组成的:
秸秆粉10、废旧木粉40、γ-(2,3-环氧丙氧)丙基三甲氧基硅烷10、催化剂0.01、丙烯酸6、松香3、8-羟基喹啉1、四丁基溴化铵0.04。
所述的催化剂为浓度为96%的盐酸水溶液。
所述酯改性木粉的制备方法,包括以下步骤:
(1)取γ-(2,3-环氧丙氧)丙基三甲氧基硅烷,加入到其重量20倍、35%的甲醇水溶液中,搅拌均匀,得硅烷溶液;
(2)取秸秆粉、废旧木粉混合,加入到浓度为0.7mol/l的氢氧化钠溶液中,浸泡2小时,出料,常温干燥,得预处理粉料;
(3)取上述预处理粉料,加入到硅烷溶液中,超声1小时,加入催化剂,在60℃下保温搅拌5小时,出料冷却,得改性分散液;
(4)取松香,加入到其重量15倍的无水乙醇中,送入到55℃的恒温水浴中,搅拌溶解,加入8-羟基喹啉,搅拌均匀,出料,与上述改性分散液混合,搅拌均匀,加入丙烯酸,送入到反应釜中,加入四丁基溴化铵,调节反应釜温度为115℃,保温搅拌2小时,出料冷却,旋蒸,除去溶剂,即得所述酯改性木粉。
所述板材的制备方法,包括以下步骤:
将废旧PVC料经过分选后干燥,磨粉,与硬脂酸钙混合,在100℃下预热20分钟,加入聚四氟乙烯粉、发泡剂、酯改性木粉搅拌均匀,送入到挤出机中,熔融挤出,冷却,即得。
实施例2
一种低成本废料回收PVC木塑板材,它是由下述重量份的原料组成的:
废旧PVC料200、酯改性木粉40、硬脂酸钙6、壬二酸二辛酯7、聚四氟乙烯粉4、ac发泡剂15。
所述酯改性木粉是由下述重量份的原料组成的:
秸秆粉20、废旧木粉50、γ-(2,3-环氧丙氧)丙基三甲氧基硅烷3、催化剂0.02、丙烯酸9、松香4、8-羟基喹啉2、四丁基溴化铵0.05。
所述的催化剂为浓度为98%的盐酸水溶液。
所述酯改性木粉的制备方法,包括以下步骤:
(1)取γ-(2,3-环氧丙氧)丙基三甲氧基硅烷,加入到其重量30倍、40%的甲醇水溶液中,搅拌均匀,得硅烷溶液;
(2)取秸秆粉、废旧木粉混合,加入到浓度为1mol/l的氢氧化钠溶液中,浸泡3小时,出料,常温干燥,得预处理粉料;
(3)取上述预处理粉料,加入到硅烷溶液中,超声2小时,加入催化剂,在70℃下保温搅拌7小时,出料冷却,得改性分散液;
(4)取松香,加入到其重量20倍的无水乙醇中,送入到60℃的恒温水浴中,搅拌溶解,加入8-羟基喹啉,搅拌均匀,出料,与上述改性分散液混合,搅拌均匀,加入丙烯酸,送入到反应釜中,加入四丁基溴化铵,调节反应釜温度为120℃,保温搅拌3小时,出料冷却,旋蒸,除去溶剂,即得所述酯改性木粉。
所述板材的制备方法,包括以下步骤:
将废旧PVC料经过分选后干燥,磨粉,与硬脂酸钙混合,在120℃下预热30分钟,加入聚四氟乙烯粉、发泡剂、酯改性木粉搅拌均匀,送入到挤出机中,熔融挤出,冷却,即得。
性能测试:
本发明实施例1的低成本废料回收PVC木塑板材:
拉伸强度:56.6MPa;
冲击强度:12.35KJ/m2;
断裂伸长率:6.1%;
弯曲强度:23.3MPa。
本发明实施例2的低成本废料回收PVC木塑板材:
拉伸强度:59.7MPa;
冲击强度:14.11KJ/m2;
断裂伸长率:6.4%;
弯曲强度:24.0MPa。
Claims (2)
1.一种低成本废料回收PVC木塑板材,其特征在于,它是由下述重量份的原料组成的:
废旧PVC料130-200、酯改性木粉30-40、硬脂酸钙4-6、壬二酸二辛酯5-7、聚四氟乙烯粉3-4、ac发泡剂10-15;
所述酯改性木粉是由下述重量份的原料组成的:
秸秆粉10-20、废旧木粉40-50、γ-(2,3-环氧丙氧)丙基三甲氧基硅烷10-13、催化剂0.01-0.02、丙烯酸6-9、松香3-4、8-羟基喹啉1-2、四丁基溴化铵0.04-0.05;
所述的催化剂为浓度为96-98%的盐酸水溶液;
所述酯改性木粉的制备方法,包括以下步骤:
(1)取γ-(2,3-环氧丙氧)丙基三甲氧基硅烷,加入到其重量20-30倍、35-40%的甲醇水溶液中,搅拌均匀,得硅烷溶液;
(2)取秸秆粉、废旧木粉混合,加入到浓度为0.7-1mol/l的氢氧化钠溶液中,浸泡2-3小时,出料,常温干燥,得预处理粉料;
(3)取上述预处理粉料,加入到硅烷溶液中,超声1-2小时,加入催化剂,在60-70℃下保温搅拌5-7小时,出料冷却,得改性分散液;
(4)取松香,加入到其重量15-20倍的无水乙醇中,送入到55-60℃的恒温水浴中,搅拌溶解,加入8-羟基喹啉,搅拌均匀,出料,与上述改性分散液混合,搅拌均匀,加入丙烯酸,送入到反应釜中,加入四丁基溴化铵,调节反应釜温度为115-120℃,保温搅拌2-3小时,出料冷却,旋蒸,除去溶剂,即得所述酯改性木粉。
2.根据权利要求1所述的一种低成本废料回收PVC木塑板材,其特征在于,所述板材的制备方法,包括以下步骤:
将废旧PVC料经过分选后干燥,磨粉,与硬脂酸钙混合,在100-120℃下预热20-30分钟,加入聚四氟乙烯粉、发泡剂、酯改性木粉搅拌均匀,送入到挤出机中,熔融挤出,冷却,即得。
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