【作者】 谢大勇；

【导师】 缪宗华；

【作者基本信息】 福建农林大学 ， 森林工程， 2004， 硕士

【摘要】 利用竹纤维与聚丙烯(PP)进行复合，研制高性能竹塑复合建筑模板(壳)材料对促进我国建筑模板工业的发展，拓展竹材应用领域，改造传统的竹材产业提高其附加值，具有积极的意义。 在本论文的研究中，采用绿竹爆破浆纤维与PP进行共混复合加工以研制竹塑建筑模板材料。针对目前研究中的不足(爆破处理对纤维形态的影响、竹纤维在塑料熔体中的分散困难，竹塑相容性差)，结合竹塑共混加工生产竹塑复合建筑模板的技术要点，进行了以下四个方面的研究。 (1) 绿竹爆破法高得率浆的研究。采用适当预处理和爆破工艺，可以制得得率80％以上，裂断长大于3300μm的绿竹爆破浆。 (2) 竹塑复合材料复合工艺及性能研究。(a)比较采用双螺杆挤出机混炼工艺与密炼机混炼工艺两种复合加工工艺对复合体系力学性能的影响。结果表明：竹纤维与PP粉，并添加适量相容剂在高速混合机中共混得到初混料片，经双螺杆挤出切粒，最后注塑或模压成型，能够实现竹纤维在塑料熔体中的分散及改善竹塑间的相容性，是竹塑复合材料开发较为合理的加工方法。(b)采用单因素试验法安排试验，考察竹塑配比、相容剂含量两因子对竹塑复合体系物理力学性能的影响。结果表明：在合适的范围内竹纤维含量的增加有助于提高竹塑复合材料的主要力学性能，在本试验条件下，竹纤维含量40％左右弯曲强度和弯曲模量达到极大值(相对于纯聚丙烯弯曲强度提高35％，弯曲模量提高两倍多)；竹纤维含量的增加，可明显提高材料的耐热性(竹纤维含量50％时材料热变形温度相对于基体塑料可提高37℃)：竹纤维增加会使熔体流动速率下降，增加加工难度。适量相容剂有助于提高复合材料性能，相容剂用量为7％时，竹／PP复合体系拉伸强度比未加相容剂时提高了约15％，缺口冲击强度比未加相容剂的提高了约20％。综上所述，竹塑复合材料中合理的竹塑配比为3：7、4：6、5：5；相容剂的合理含量为6％～8％。 (3) 竹塑复合材料相容性及其复合机理研究。通过示差扫描量热仪(DSC)的分析及扫描电镜(SEM)的观察，证明了相容剂的确改善了竹纤维与PP的相容性，提高了竹塑复合体系的粘结强度：在适量相容剂的作用下，竹纤维能够发挥其比强度高的特点，对基体塑料具有增强的作用，从而使竹塑复合摘要材料整体力学性能相对于基体塑料有较大提高。 (4)竹塑复合材料建筑模板性能研究。采用正交试验法安排试验，考察竹塑配比、板坯密度、热压温度和热压时间四因素对竹塑复合建筑模板材料的物理力学性能的影响，并进行验证试验。可以得出，竹塑复合建筑模板材料的合适制造工艺参数为:竹塑配比5:5，板坯密度1.09/cm3，热压温度200℃，热压时间15min。研制的竹塑复合建筑模板材料主要物理力学性能(弹性模量除外)达到并超过我国现行的“混凝土模板用胶合板”优质材执行标准(GB八7656一1999)中的技术指标要求，静曲强度达31.IMpa(指标值:24Mpa)、内结合强度达4.OMpa(指标值:1 .OMpa)、吸水厚度膨胀率为0.41%(指标值:4%)，冲击强度达36.6Mpa，但弹性模量偏低。更多还原

【Abstract】 Utilizing the fibre of bamboos and polypropylene (PP ) to make the high-performance building formwork of bamboo/plastic composite ,which promotes the development of building formwork industry of our country, lightens the old and useless plastics pollution to the environment, expands the bamboo application, transforms traditional bamboo products industry to improve its added value.In this article , the following four researches are accomplished to discover a suitable technology to manufacture the bamboo-plastic composite of building formwork, which overcomes the drawback( effect of explosion treatment to fiber morphology, the scattering in the plastic melting ,bamboo fibre bad compatible to plastic).1)Study on high-yield pulping of green bamboo with steam explosion process. The result shows that explosion pulp of breaking length up to 3300um and yield up to 80% is obtained by suitable processing condition of pretreatment and steam explosion.2)Study on the compound technique and the performance of bamboo/plastic composite.( i )compairing two processing technology of double-screw extruding machine technology with interal batch mixer technology, Its result shows mixing bamboo fibre ,PP powder, and right dosage of compatible materials in high-speed mixer , pushing and granulating, mould pressing and sample-making, can realize bamboo fibre scattering in plastic melting body and improve bamboo plastic compatibility. It is suitable processing technology for bamboo/plastic composite. (ii)Adopt single factor experimental way to test, investigate bamboo plastic matching , compatible materials dosage two factor’s influence on the performance of bamboo/plastic composite. The result shows: increasing bamboo fibre content, bamboo/plastic composite mechanics performance is on the rise, when bamboo fibre charge is 40% flexural strength reaches maximum (raise for the pure polypropylene by 35%); Increase the bamboo fibre, can improve heat resistance of material obviously (material hotout of shape temperature can raise for the base body plastics by 37 C when bamboo fibre charge was 50% );The rise of bamboo fibre can make melt flow rate drop , increase difficulty of processing. The right dosage of compatible materials contributes to improving composite performance, compatible materials charge was 7%, 30% bamboo / PP composite tensile strength raise about 15% , elongation at break raised about 20%.3)Bamboo/plastic compatibility and mechanism analysing. The analysis results by means of DSC and SEM indicate that the compatible material improves the compatibility bamboo fibre and PP really, and raises the strength of forming of the system; When compatible material dosage is right, bamboo fibre can reinforce plastics , make bamboo/plastic composite mechanics performance improve a lot for the base body plastics.4) Study on the building formwork of bamboo/plastic composite. The orthogonal design is adopted to investigate the influence of bamboo-plastic matching, board density , hot pressing temperature and hot pressing time four factors on building formwork. The result indicates that the optional conditions of manufacturing building formwork of bamboo/plastic composite are: the bamboo-plastic matching 5:5, the density 1.0g/cm3, hot pressing temperature 200 C, hot pressing time 15min. the building formwork of bamboo/plastic composite physics mechanics performance exceed " plywood for concrete form " the not high-quality material last standard (GB/17656-1999 ), flexural strength is 31.1Mpa, combine intensity is 4.0Mpa, absorb water thickness is 0.41%, but the elastic amount is on the low side.更多还原