Relationship Of Shear Histroy, Morphology – Microstructure And Mechanical Properties Of Micro Injection Molded Parts
The relationship of shear history, morphologymicrostructure and mechanical properties of the microscale parts was investigated based on the polypropylene parts with thickness 0.2mm and 0.5mm molded under varied injection speed. Shear rate was analyzed using Moldflow. 0.5 mm parts showed skin-core structure in the thickness direction with imperfect shish-kebab structure appeared in the transition layer between skin layer and core layer, however, the transition layer of 0.2 mm parts shows columnar crystal. The whole shear level in shear history increased with injection speed increasing for all the parts with two thicknesses. The ratio of skin layer of 0.5 mm parts decreased as the injection speed increased, which result in the decreasing of yield stress, modulus, breaking strength and elongation at break. The ratio of skin layer of 0.2 mm parts increased with injection speed increasing, and results in increasing of yield stress, modulus and breaking strength, and decreasing of elongation at break.
Morphological comparison of isotactic polypropylene parts prepared by micro‐injection molding and conventional injection molding
The morphological feature of microparts evolved during micro-injection molding may differ from that of the macroparts prepared by conventional injection molding, resulting in specific physical properties. In this study, isotactic polypropylene (iPP) microparts with 200 µm thickness and macroparts with 2000 µm thickness were prepared, and their morphological comparison was investigated by means of polarized light microscopy (PLM), scanning electron microscopy (SEM), differential scanning calorimeter (DSC), and wide-angle X-ray diffraction (WAXD). The results presented some similarities and differences. PLM observations showed that the through-the thickness-morphology of micropart exhibited a similar “skin–core” structure as macropart, but presented a large fraction of shear layer in comparison to the macropart which presented a large fraction of core layer. The SEM observation of shear layer of micropart featured highly oriented shish-kebab structure. The micropart had a more homogeneous distribution of lamellae thickness. The degree of crystallinity of the micropart was found to be higher than that of the macropart. High content of β-crystal was found in micropart. The 2D WAXD pattern of the core layer of macropart showed full Debye rings indicating a random orientation, while the arcing of the shear layer indicates a pronounced orientation. The most pronounced arcing of the micropart indicates the most pronounced orientation of iPP chains within lamellae. Copyright © 2011 John Wiley & Sons, Ltd.
Subject index
Adoptive immunotherapy A1, A63, A63, A64, A64, A65, A66, A68, A69, A69, A70, A70, A71, A71, A72, A72, A73, A73, A74, A75, A76, A78, A79, A79, A7, A80, A80, A81, A81, A82, A84, A85, A86, A86, A88, A88, A89, A90, A90, A91, A92, A93, A93, A94, A95, A95, A96, A96, A97, A97, A98, A98, A99, A99, A102, A103, A104, A104, A166, A167, A169, A170, A174, A177, A179, A181, A182, A199, A204, A205, A21, A215, A220, A231, A231, A243, A251, A254, A25, A276, A287, A304, A307, A310, A315, A316, A316, A329, A331, A333, A357, A358, A369, A405, A441, A442, A458, A458, A459, A459, A461, A461, A463, A468, A468, A479, A492, A497, A497, A56, A58, A58, A59, A60, A60, A61, 1, 100, 101, 102, 103, 104, 106, 109, 111, 112, 113, 114, 115, 116, 117, 119, 120, 122, 123, 124, 125, 127, 128, 129, 13, 130, 131, 133, 134, 136, 139, 140, 141, 142, 146, 147, 148, 149, 150, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 163, 164, 165, 166, 167, 169, 173, 174, 175, 272, 273, 278, 280, 285, 290, 293, 297, 298, 324, 333, 335, 35, 353, 360, 379, 380, 400, 414, 418, 42, 454, 470, 493, 500, 504, 513, 515, 516, 542, 545, 549, 598, 599, 614, 675, 737, 739, 764, 765, 766, 767, 770, 771, 772, 780, 781, 801, 822, 830, 831, 89, 91, 92, 94, 95, 96, 98 Angiogenesis A108, A155, A171, A200, A201, A214, A228, A265, A305, A349, A350, A359, A410, A47, A48, A480, A483, A519, A5, 181, 257, 281, 327, 328, 351, 374, 435, 495, 583, 584, 602, 683, 76, 78, 802, 808, 873, 9 Antibody A7, A73, A81, A86, A91, A8, A99, A9, A104, A108, A108, A109, A109, A111, A115, A119, A126, A128, A130, A135, A138, A141, A144, A151, A153, A159, A160, A163, A164, A164, A171, A172, A175, A176, A2, A187, A193, A193, A195, A195, A198, A199, A20, A209, A212, A225, A229, A230, A23, A233, A233, A235, A239, A239, A240, A242, A244, A244, A245, A245, A246, A247, A247, A24, A250, A256, A260, A261, A266, A267, A268, A269, A273, A275, A286, A288, A292, A293, A296, A299, A300, A307, A3, A308, A31, A318, A324, A35, A334, A334, A336, A338, A339, A342, A343, A344, A344, A346, A346, A351, A351, A353, A356, A360, A361, A363, A368, A369, A370, A371, A372, A372, A373, A374, A376, A377, A378, A378, A379, A379, A380, A380, A388, A391, A399, A399, A41, A402, A410, A410, A411, A412, A414, A417, A418, A419, A419, A420, A422, A422, A423, A426, A427, A428, A428, A430, A431, A432, A434, A434, A435, A446, A454, A455, A459, A463, A465, A468, A468, A469, A474, A481, A483, A50, A486, A487, A491, A502, A502, A504, A507, A507, A508, A510, A511, A512, A512, A516, 12, 122, 133, 141, 151, 16, 167, 17, 174, 181, 182, 184, 185, 188, 195, 203, 210, 215, 218, 227, 231, 237, 243, 250, 253, 261, 262, 265, 267, 268, 281, 282, 287, 288, 3, 305, 313, 315, 317, 318, 323, 325, 34, 342, 348, 369, 377, 378, 38, 384, 385, 387, 393, 394, 395, 399, 401, 402, 403, 404, 405, 406, 407, 41, 412, 421, 428, 429, 438, 439, 442, 443, 450, 453, 469, 472, 476, 478, 480, 483, 486, 499, 5, 501, 51, 519, 531, 55, 550, 552, 557, 561, 562, 569, 571, 572, 573, 576, 578, 586, 587, 590, 594, 603, 605, 607, 612, 615, 616, 617, 618, 619, 621, 622, 626, 629, 630, 631, 632, 633, 634, 635, 647, 653, 665, 666, 67, 670, 683, 684, 686, 687, 690, 693, 696, 697, 698, 699, 702, 703, 704, 711, 713, 714, 715, 718, 721, 722, 725, 726, 727, 745, 757, 760, 766, 772, 776, 780, 781, 785, 793, 804, 808, 81, 812, 814, 820, 842, 843, 846, 851, 852, 853, 856, 858, 860, 861, 869 Antigen presenting cells A67, A79, A80, A92, A95, A96, A99, A99, A101, A102, A102, A108, A108, A111, A129, A139, A160, A166, A177, A178, A183, A191, A191, A213, A220, A221, A245, A254, A256, A262, A266, A275, A314, A322, A327, A328, A35, A335, A345, A359, A359, A360, A361, A364, A366, A368, A369, A371, A372, A403, A409, A411, A411, A418, A422, A433, A449, A48, A468, A471, A472, A4, A50, A495, A502, A506, A513, A514, A515, 108, 128, 130, 153, 157, 160, 166, 167, 168, 169, 170, 181, 182, 188, 217, 235, 263, 271, 290, 291, 299, 310, 311, 349, 360, 362, 404, 418, 421, 431, 438, 453, 510, 526, 538, 540, 55, 553, 575, 601, 602, 603, 605, 610, 611, 612, 615, 617, 618, 672, 682, 685, 686, 695, 703, 724, 748, 78, 780, 787, 790, 8, 81, 828, 842, 849, 862, 864, 868 Autoimmunity A8, A116, A15, A180, A181, A22, A380, A387, A394, A395, A402, A408, A502, A510, 16, 197, 27, 295, 296, 37, 637, 645, 657, 658, 671, 680, 843, 856