Issue link: https://iconnect007.uberflip.com/i/1181966
76 SMT007 MAGAZINE I NOVEMBER 2019 Even more thermally massive boards—fea- turing high layer count and or heavy weighted ground planes, which require rework while meeting the original inspection criteria post- rework—are challenging in terms of hole fill and keeping neighboring areas from thermal damage. Neighboring devices are getting closer and closer together in their board layout, creat- ing challenges in PCB rework—especially when it comes to RF circuits, handheld devices, and IoT products. The continued upward trend of these technologies will become more numer- ous and pronounced. There are several changes we are consider- ing in planning for our business in the com- ing years where these rework challenges will exist. Like almost all highly skilled labor forces in America, much of the workforce is approaching retirement age, and we need to make sure that we continue bringing the skill level of our employees up (e.g., 55 is the aver - age age of a welder and age 57 is the aver- age for tool and die makers). This same prob- lem exists in the PCB process assembly arena where skilled process engineers are in this same age bracket. How will they be trained? How will the industry attract and train rising talent? We are now in our 122 nd month of economic expansion, and what comes up must come down. The landing will likely occur sometime in the next few years. Will it be a crash land - ing or a soft landing? How will we retain the employees who we are "bringing up" in the ranks during an economic softening? Some of the newer, high-growth technologies will con - tinue to require attention in terms of the devel- opment of rework processes for flex circuits, embedded layer actives/passives, and the pro- liferation of micro-component packages. Many times the industry "figures out" a process before the rework and repair standards can catch up. Lastly, with continued pressure on having enough highly trained personnel, an oppor- tunity exists to reduce costs with respect to some hand soldering skills, AI or VR training, EOS/ESD and acceptability criteria. This is an opportunity to get the labor force skills up at a reasonable cost. SMT007 Bob Wettermann is the principal of BEST Inc., a contract rework and repair facility in Chicago. For more information, contact info@solder.net. To read past columns or contact Wet- termann, click here. and ions, such as fluoride. Jeremiah Johnson, the senior author of the study, says, "The nice part is that it works using the standard ROMP workflow; you just need to sprin- kle in the new monomer, making it very convenient." Potential uses include not only medical applications but also the synthesis of industrial polymers that would break down more rapidly after use, the researchers say. In tests in mice, the research- ers found that during the first week or two, the degradable polymers showed the same distribution through the body as the original polymers, but they began to break down soon after that. (Source: MIT News Office) MIT chemists have devised a way to synthesize poly- mers that can break down more readily in the body and in the environment. A chemical reaction called ring-opening metathesis polymerization (ROMP) is handy for building novel polymers for various uses such as nanofabrication, high-performance resins, and delivering drugs or imag- ing agents. The resulting polymers, however, do not nat- urally break down in natural envi- ronments, such as inside the body. The MIT research team makes those polymers more degradable by adding a novel type of building block or monomer to the backbone of the polymer/structure forming chemical bonds that can be bro- ken down by weak acids, bases, New Synthesis Method Yields Degradable Polymers